Have you played Shamrock's Ness? I don't think you would call him bad if you had.
That was something of a joke as Ness is probably top 15 imo, I'm just salty he wasn't as fun to play as his PM version.
I do think the rest need buffs though.
Fox and Falco should have their lasers buffed and shines brought back to Melee-level but with a cooldown to prevent multishines (I'd also let Falco Phantasm/Fox Illusion be cancellable into A moves on hit but I don't know if they've actually need that). Also make Falco's NAir a proper multihit move.
G&W should be able to cancel Fire into an aerial at any time rather than just at the apex of the jump and I'd probably give him less endlag on his FAir and BAir, haven't really played this character much lately so I don't know exactly what he should have really.
DK's roll shouldn't stop him at the edge and it should be cancellable into a jump in the air or on hit, I'd reduce the endlag and knockback on his UThrow as well and increase the knockback on a DK punch.
Zelda phantom should be storable, I'd remove special fall on Din's Fire and have the BAir hitbox match the FAir.
Ganondorf's Choke Slam hitbox should be increased in size and last longer so it doesn't whiff at the end as much and his UTilt should be changed so that you can also activate the kick by pressing A again, with it's power being relative to how long it charged.
Toon Link I'd reduce the knockback and endlag on his BAir as well as bring back the DSmash gimp from Brawl and make his DAir bounce again.
Samus should have her bombs explode on contact again, her grab end lag on whiff should be reduced, DTilt should have kill power, her NAir should be a sex kick again and the knockback on jab1 should be reduce and set.
Marth just needs reduced endlag on his aerials and throws so he feels a bit more fluid again.
Metaknight should just not be shit, they didn't need to nerf him as hard as they did, just give him a bit more range and reduce some of the endlag on his moves that now have massive endlag.
Little Mac's Up Special shouldn't put him into special fall, maybe increase his weight as well.
I'd want Ness to have his old yo-yo returned and decrease the startup on his Dair, but then he's probably be way too good.
Olimar's Up Special shouldn't put him into special fall if he cancels it with an aerial, reduce the landing lag on Dair and UAir and increase the range on his pikmin aerials.
Dr. Mario needs his Dr. Tornado endlag reduced so that he can actually recover again and I'd increase his movement speed and damage on pills.
For Megaman I'd change his forward smash to the Megaman X Hadouken that doesn't travel nearly as far as his current forward smash, then I'd change his megabuster so that it starts charging if you hold A, letting you move and jump whilst still charging it, damage and knockback would obviously be less than it currently is for his forward smash, crash bomber shouldn't be transferrable either.
I dunno, I feel like there's a lot of things about this game I'd make if I had the ability to.