Here are some characters whom I want out. Color me negative, but here I go anyway:
Captain Falcon, and everything related to F-Zero. Purge the whole series' presence and let it die with some dignity.
Captain Joke Character's presence in SSB isn't helping the F-Zero series at all, but murdering it, cold-blooded. People don't even bother to look into the series as a result of his moves being the way they are (USE THE GUN ALREADY).
And Sheik:
1. Huge spoiler for OoT.
2. She was an NPC at best in that game, doing nothing but providing Link with warp songs.
And as a result, people only like and care about her in Melee & Brawl, not in OoT. I don't care if she is Zelda (hence the first point). Just change Zelda's Down special to something else. And lastly, this is causing people to expect Sheik to appear in another Zelda game, which she never will. Ever.