One general change I'd like them to make is removing the chance of getting doubles of custom specials you already have. Its so goddamn stupid and there is no point. I bet most people won't ever experience all the custom moves due to how much of a pain it is to get them.
Buffs
Give
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less lag on his jab, preferably how it was in Melee. INSTAPUNCH
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Increase sweetspot hitbox for lightning kick, make din's fire overall more useful and give fair less landing lag. And they should change the Din's Blaze custom so Zelda can move around more after its placed, like in Project M.
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Make Pikmin unable to be reflected. Its so stupid!
Return
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's down smash to its former glory. Give fair less landing lag to compensate for its low power. Give f smash sourspot more power.
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Buff recovery immensely. Increase vertical lift and steering ability on all up B variants, increase horizontal distance on all side b variants.
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Buff final smash. I don't care what the hell they do to it, just don't make it completely counterproductive!
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Give aerials less landing lag.
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Make less laggy in general.
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Give more range on smashes
Nerfs
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Nerf. Hoo. Hah. Give uair more ending lag.
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Everything.
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More landing lag on aerials.
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Nerf lightweight. Its disgusting.