If Melee didn't exist, Brawl would now be Melee.
That's really all I gotta say about it. Melee was an attempt to take the N64 gameplay and make it more complex, in-depth and exciting (pretty much the most obvious next step if you don't want to make a quick rehash) and Brawl was toning it down a bit after Sakurai felt like he took the idea too far. It was basically bound to happen, so if Melee hadn't been a thing, Brawl would likely be the game with the fast gameplay and complicated advanced mechanics. You don't learn from your experiments if you don't experiment in the first place. Melee is the experiment in this case. Brawl is too to some extent, but Sakurai had a clearer vision on where he wanted to take the series because of Melee.
So it's not as simple as that. If Melee didn't exist, Brawl would most likely be a completely different game.
That's just completely off...
Melee wasn't designed to be significantly more complex then 64, and these "techniques" weren't supposed to be used. Doubt L-canceling was supposed to be anything beyond an Easter Egg...
Brawl would likely of been some freakish mix of Melee and the real Brawl. More then likely Wavedashing would of been squashed mid-development with the extra time, considering it was "left in" mid development, and L-canceling removed because of online (assuming this is on the Wii of course). Fall speed could really go either way, but no doubt defensive actions would be buffed to match the more powerful items. Wether or not air-dodging would be Melee or Brawl's would be hard to say, but it would certainly exist in some form.
Anyway, most of the Melee clones wouldn't be there at all. Dorf would probably be what's currently Ike and Marth would be the sole FE character. Shiek wouldn't be there at all, and Zelda would probably have a completely different moveset (but not necessarily better then what she has now). TL would probably be there, maybe less of a clone. ICs probably wouldn't of made the cut (to better optimize the game) and 8-player Smash would of came a generation early at the cost of graphics. Peach and Bowser would probably be like their Brawl versions, and then Mewtwo would probably be playable with a better moveset.
With the Brawl characters, not too much would be different. Wolf would probably get in over Falco and be somewhere between the two. Lucas probably wouldn't of been added because they never had plans to replace Ness in Melee. PKMN Trainer and ZSS wouldn't get in either because of transformations not being possible with 8-player Smash, but Charizard would probably be playable with Mewtwo, Lucario, and probably another gen 4 mon. Miis might of been implemented early, but Villager probably wouldn't of. ROB and G&W might of had to fight for a spot. The Brawl newcomers otherwise wouldn't of been changed that much, but a Kirby character and Olimar might of been put off for later. Meawl would of had less characters then Brawl due to a lack of pressure to add a bunch, but much more full characters then Melee because they wouldn't need to pad things out with clones.
Smash "4" would probably be further corrective of Meawl, but how it'd play is impossible to peg. Chrom
may of had a shot over Robin since there's so few FE characters, Mewtwo probably wouldn't of been cut, and Snake might of not been cut either since the series would of went a long time without cuts. Alph would of been playable before Doc, which could possibly effect Lucina and Dark Pit depending on how much more or less time they put into him compared to Doc. The overall more popular (or more accurately, less divisive) Ninten would of been a Ness alt without any voice differences due to ease of adding and to give the obscure and finished series some more love. Metroid would still be at one rep because TOO BIG, Jr. wouldn't of made it due to his "bottom of the barrel" status Sakurai hinted at, and Mac probably wouldn't of either due to comparitively little demand and lack of an apparent moveset. Shulk is about 50/50, depends on how many characters they'd want to add.