Another idea that occured to me yesterday was why not have almost all Pokemon coupled with a Trainer? You would select Pokemon Trainer on the screen, and then be able to pick out of a few sets of trainers with each diferent Pokemon. Example I thought of was:
Red - portraited as the male trainer you play as in Pokemon Fire Red and Leaf Green
-Has a Squirtle, Ivysaur and Charizard. Playstyle almost like it was in Brawl but with a few tweaks.
-Down B is no longer a switch between the characters but it'd be done differently (no ideas how to do this yet) and you'd be able to choose which Pokemon you'd want.
-Charizard will have a few more faster attacks, a better Flametrhower which is also usable in the air. More jumps / better flying (make it feel more natural) and make him lighter perhaps with a new Down and Side B.
Idea for Down B would be Overheat, which would work as a 'build up' move like Wario's Down B basically. You'll notice when Charizard's Overheat is at full power when his tail's flame flares up a lot bigger than usual. And you can build up power with it when pressing B while doing the move to increase range and knockback, but Charizard would eventually hurt himself (10%) for doing this, but it's... very strong. After Overheat is done, Charizard's Flamethrower also is all used up.
Side B is Wing Attack, which'll send a small tornado similar to the one on Hyrule Castle on 64 but just for 5 seconds long and less power overall. Can be used to trap enemies in the Tornados and block projectiles. One of Zard's faster attacks also.
Up B can also be used in the air as a slamming move like Bowser and Yoshi's Down B, but less powerful in terms of knockback.
-Squirtle's B will do damage now to with some light knockback but the same properties and he will 'inherrit' Pikachu's Skull Bash instead of Pikachu. It isn't as powerful as Pikachu's version, and it doesn't travel as far however.
His down B would be Widraw and is a defensive move that works as a quicker shield, but Squirtle would still be able to be knocked back. Fastest move in the game! Can be used in the air, but you'll even be able to get knocked away faster. You'll receive no damage at all from shielding with this. But it of coarse recuires practice because staying in the shield can still get you killed. Less advantagous at higher %s.
-Ivysaur will have better Razor Leafs (more similar to the Chikorita Pokeball-Pokemon from previous games) and a Down B involving spores (Stun Spore, Poision Powder, Sleep Powder) which will each cause different effects. Stun Spore would act a lot like the paralysis from Zero Suit Samus's gun, Sleep Powder turns foes into sleep, and Poison Powder causes a 'poison' effect that can last from 10 to 30 seconds max.
-Like Lucario's Aura, the Pokemon of Red get stronger B moves (slightly) when they are over 100% damage.
Yellow : (no idea which trainer would portay as him, possibly also Red- but called Yellow)
-This trainer will take the place of Pikachu, and Pikachu will be his main fighter. However, this Pikachu is able to evolve during battle, and you'll start out with just Pichu, who is able to become Pikachu when it's 'happy'.
-You'll start with Pokemon Trainer Yellow with Pichu only. After beating Classic Mode (or whatever there is) with Pichu, you have to fight Pikachu to unlock him, or being able to evolve into Pika. Clear Classic Mode or another mode with Pikachu, and you'll fight Raichu, and from this point can evolve Pikachu to Raichu.
-In a way Pikachu alone is also still playable as a more 'balanced' version of this whole character. When going into VS mode, pick Pokemon Trainer, select Yellow and click on Pikachu on the cursor instead of the trainer. You will not start out as Pichu, but won't be able to evolve into Raichu either.
-All 3 Pokemon will have all the same moves, but each version is slightly different, making them all clones of each other, but with as much difference between them as Pichu and Pikachu had in Melee.
-Pichu is one point lighter than Jigglypuff, and smaller than Olimar. Pikachu is somewhat lighter than he is now, and just a little bigger than Olimar (making him smaller than in Brawl) but Raichu is about in between what Falco and Zelda are now. Raichu represents more the way Pikachu played as in the other Smash games.
-The new Forward B of Pikachu / Pichu / Raichu is Thunder Wave, and B is a chargable move from now on. Thunder Wave is a stunning move which looks much like the animation of Thunder Jolt, but it's a yellow bolt instead, does lesser damage but causes a stun longer than ZSS's gun. This is the only move that is completely the same for all 3 Pokemon.
-Pichu will be very weak as he was in Melee, but will have some better range on his Smashes like the F-Smash. Some moves will still hurt Pichu however, but his Up B will not cause him damage anymore, and will even cause a small speed burst when Pichu lands the floor with it to escape better. This burst of speed will make him run faster than everybody, but Sonic -if he's still in, but wears of after 3 seconds. Pichu will have some 'misfire' attacks also with Thunder and his B that sometimes discharge and cause Pichu damage but they will be very powerful in terms of damage (not knockback, which would still be subpar). Pichu evolves when it's happy, which means if it's leading in battle. If it KOs the enemy character before Pichu gets KOd, theres a 75% chance of him evolving into Pikachu. Pichu is just a little bit slower than Pikachu, but it's hardly noticable. If doing a 3 Stock match and Pichu has been KO'd before he could evolve and is on it's last stock he'll spawn the stage with a Final Smash. Which is still Volt Tackle and is the same for all 3.
-Pikachu still plays much like he does in Brawl, but Up B has 3 jumps to make up for the loss of recovering with Forward B. When landing the ground with Up B, there is less lag than before. This is the same however with Pichu and Raichu. Knockback on regular A moves is decreased on Pikachu with it's loss of size, but he still has about the same range for most moves despite being smaller. Pikachu evolves into Raichu if he finds the Thunder Stone on stage. It has a 1/4rd chance of dropping out of each KO Pikachu makes but it can't be easily seen on stage. It's almost invincible at it's a sort of luck finding it. Sometimes it glitters though, hinting where it is. You can't pick up the Thunder Stone like an item, and walking over it is the only way to evolve.
-Raichu is the heaviest of the 3, and also slightly faster than Pikachu. His attacks are a lot heavier than Pikachu's are in Brawl, and it's longer limbs and tail gives him more range. Despite being stronger, heavier and the added range, a lot of Raichu's stronger attacks have quite some lag on it. Raichu is quite the fast rushdown character, but his Up B has just 2 jumps instead of Pichu and Pikachu's 3. His playstyle resembles Pikachu's style in 64 most. His Forward Air and Neutral Air are Pikachu's moves from 64 as well, and act exactly like them.
Female Pokemon Trainer (possibly represented by the Lass, or FR/LG Female character)
-Has 3 Pokemon as well which are: Jigglypuff, Meowth and Eevee.
-You are able to select which Pokemon you send out first, and can switch between them as easily as Pokemon Trainer Red can switch between his (done differently than in Brawl)
-Jigglypuff's Rest can now also heal of damage like in Brawl Minus but ot quite as much(
http://www.youtube.com/watch?v=7D5e7fQjMpk) and it does even less knockback than in Brawl. Sing is more effective to, but Jigglypuff has now even less power than before. F-Smash is weaker, but faster, yet Jigglypuff will styll be able to dish out damage quickly with her aerials. Wall of Pain is still possible, but F-Air is weaker meaning it's more risky Better hitboxes though. Jigglypuff is the 'cleric' of the team, and with her Rest she's able to heal of damage for the rest of the team.
-Meowth is a more all around character, but still on the lighter, faster side. Is exactly Pikachu's size and weight from Brawl, but runs slower. His B is Pay Day, which works a lot like it did in Brawl in his Pokeball form. His A moves involve clawing and scratching a lot, and he can combo quite well. Fury Swipes is his Forward B and the move can combo really well. Down B is Pursuit, Meowth analyses his foe in a wild cat stance and can unleash an attack with Dark-based damage on a foe when you let go of B. When released with the enemy facing Meowth, the attack works much like Diddy's Side B Monkey Flip but the kick version of it, yet a little weaker (but faster). However, when the foe turns his back to Meowth, the move's strenght is 3 times as powerful! Takes prediction to use the move well. Can also be used as recovery like Diddy's Forward B. Up B is Meowth's version of Quick Attack, and does more damage on impact than Pichu / Pikachu Raichu.
-Eevee is the most complex character out of the 3 Pokemon the Female Trainer has. And like Pichu and Pikachu, Eevee can evolve. The difference between the A attacks between all Eevee-evolutions is basically the same, but with slight different effect on each evolution. Eevee has a lot of sub characters on it, and because of programming issues, most of the evolutions of Eevee have moves similar to the Pokemon already in! Meaning Jolteon's B moves resemble Pikachu's a lot, Flareon like Charizard (without Fly), Vaporeon like Squirtle (Acid Armor is like Widraw), Leafeon like Ivysaur (with only Posoin Powder called Toxic instead of all spores, and a different neutral B), Espeon like Mewtwo (come back to that later), Umbreon like Zoroark (come back to that later as well) and Glaceon is a little mix between Flareon and Leafeon in attacks but with Ice effects.
-Jolteon is the fastest and lightest with Espeon being second, Umbreon is the slowest and heaviest with Vaporeon being second, but all Eeveelutions are pretty similar to each other still (which makes the evolution more of a novelity at best which is not bad) in most A attacks. The real difference comes with B moves. Will explain if this idea at all is well received. Eevee, like Pikachu evolves either with elemental Stones, or happiness (only in case of Espeon and Umbreon, making them the most likely to evolve into).
-All Eevee characters share the same Up B. And keep at least one of Eevee's special moves when evolving, or at least something that resembles it in case of Return.
-Eevee's special moves are B: Return, a ramming attack with a 'love' effect like Peach's Up Tilt. Side B: Sand Attack. Down B: Double Team, similar to Lucario's attack but you're able to move with this attack. Not much of a counter-like attack than Lucario's, but it's mostly for mind games. Creates Eevee copies, and just one is the real one. It's there to confuse the enemies. Up B: Quick Attack - very similar to Meowth's, but shorter distance.
-Likewise with the Yellow Trainer, you can select Jigglypuff as a own character. Eevee can be unlocked as an own character, and so can Meowth.
Cool Trainer (as represented by: Cool Trainer)
-Has Lucario, Zoroark and Snorlax
-Lucario is like Brawl more or less. Few tweaks, but he could mostly stay the same. Lucario is the lightest of the team. But also the most straight forward fighter. The Aura power in which he becomes stronger if he's damaged stays.
-Zoroark is medium weight, but not much of a difference from Lucario. B moves I've been thinking of are Night Slash for B (straight forward cutting projectile), Fake Out for Side B (has the potential of flinching the opponent like a broken shield), a stronger version of Pursuit for Down B and Up B is U-Turn.
Lots of Zoroak's attacks resemble Meowth's regular attacks (about 60% the same), but Zoroark is slower and more powerful. Can combo just as well as Meowth.
-Snorlax is very heavy and can use Rest as well as Jigglypuff, but he relies on it far more. He's also obviously very slow, and is the strongest attacker out of all the Pokemon. Very bad jumper though. B is Sleep Talk, but if Kirby Copies Snorlax he'll do Rest instead (resembling the Sleep ability of Kirby). With Sleep Talk, Snorlax can get up while still sleeping when using Rest, but the move will have more lag on it, and he can use Sleep Talk only once each time he Rests. Side B is Mega Punch and is basically just like Jigglypuff's Pound as well. The move looks exactly like Jigglypuff does it, but with more range, and double the power (26% instead of Jiggly's 13%) and half the speed, but with super armor frames. Up B is Body Slam and is a powerful attack but doesn't work al too well for recovery. Snorlax also can not run, and only walk making him the slowest character overall in the game. Exellent for time matches as with his enormous weight and ability to heal with Rest, he's able to tank A LOT. His strenght is definitely there, but he's pretty slow overall. Could be considered like Zoroark, a sort of Luigified clone to Jigglypuff. But the main difference is of coarse Snorlax being the heaviest fighter, while Jigglypuff is the second lightest.
-All characters can be unlocked as own fighters as well, but you start out with Lucario.
-Cool Trainer will not switch out his Pokemon during battle. Each stock will be a different Pokemon for him.
Pokemon Trainer Ruby (represented by May from Ruby / Sapphire / Emerald)
-Has a Mudkip, Grovyle and a Blaziken.
-Will come up with a moveset later.
And there's Mewtwo, who is a total seperate character of himself.
In total that's about 23 playable Pokemon.
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But: most of them are clever clones of each other which is hardly noticable while playing them.