Hm, like H-J I'd like the air dodging and recovery to be like in brawl.
Online needs TO BE A LOT LESS LAGGY.
Custom stages should be removed imo, they were pretty pointless

Final Smashes should be in imo, but be A LOT MORE BALANCED. *looks at Sonic >__<* Since I do like to play with items on occasion.
Snake and Sonic should be removed imo.
As for Adventure Mode, I don't really mind which style they choose but they better not make certain moves better in the Adventure mode. Like in Brawl, Yoshi's Grab Range is somewhat better in SSE than in multiplayer :p
No more chain grabs/infinites.
Characters and Match-ups being a lot more balanced.
Tripping should be gone.
Less spammy moves.
(Yes I know this is a lot XD)