leekslap
Smash Ace
Um...The further PM gets away from Melee the less popular it becomes. Bringing back Melee top tiers to how they were in Melee is what drove many people to PM in the first place. Mess with that and people will go back to Melee. Making everyone else on the level of Fox, Falco, Marth, Peach, Shiek, Jigglypuff and Captain Falcon while keeping those characters as close the their Melee counterparts as possible should be what PM strives for.
Peach and Captain Falcon are perfect the way they are. Even Fox and Falco are perfect the way they are (Though they could use their first frame shine invincibility back and removing the decay on laser damage). Marth is pretty good, in fact he too would be perfect if his Dancing Blade wasn't so different from how it was in Melee. Shiek should get the hurtboxes back on her needles and their Melee properties should return in full glory.
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Being close to Melee has next to nothing to do with popularity. If you don't like how your main is in Project M and/or Smash 4 then you find another character like how we've been doing it for ALL the Smash games. ZeRo's character got nerfed completely and changed radically in Project M so he switched to Pit and dominates all the tournaments. Denti's character got straight up cut from Smash 4 and he kicks butts with his new Sheik! Or you could just adapt like ESAM and Plup adapted to Samus and Gimpyfish adapted to Bowser. Heck even Mango adapted to Falco in Bra-... You-Know-What, and ZeRo still mains Fox in Smash 4 despite lacking all the things that made Fox what he is in Melee.
I don't know much about Peach, but I'd die of happiness if Falcon got some stuff from 64.
Do you even know what a shine is? It's an ultra fast ( spike ) move that opens up a whole new world of pressure, movement, and combos ( including a combo that literally renders you helpless in hitstun ) and is near impossible to punish since it is jump cancelable and you want to make it invincible?
Also, people need to shut up about nerfing Fox and especially Falco. The only nerf I find reasonable is to nerf Fox's up smash. No nerfs to up air or complete reimagings or stuff like that.