Melee check-in: I kind of like this roster better than the official one, honestly. It perhaps leans a bit too much towards Mario-adjacent characters, but my only (and admittedly pretty minor) gripe here might be with DK Jr. If anything, the roster might be a bit lacking in terms of Zelda characters, but I'd rather save Ganondorf for a game where he could actually shine instead of having him being our own Falcondorf.
The clones are interesting and definitely a highlight. I particularly appreciate Daisy and Celica, though Black Shadow deserves a mention. It's fun that we actually kept Pichu, because I actually really like its presence in Melee and I think it was an great way to highlight in a low-effort character both Gen 2 of Pokémon and its most influential mechanic, breeding.
Probably the only character I would have not confirmed from Melee is G&W. Don't get me wrong, I like the character, but I think that, with the roster we currently have, a more standard NES character would have made for a better choice. Sakurai's idea of Ice Climbers was ingenious, though I would have probably personally gone with Little Mac, being a somewhat popular NES title with strong ties to fighting games (though Punch-Out arguably wasn't a fighting game).
Job #13: Ok, Sonic ought to stay in the game, he is definitely the most iconic non-Nintendo character they could have added to the game to still make Brawl a celebration of Nintendo's history.
As for Snake... I don't know... I mean, my personal bias says that we should have 3rd party characters that still feel like Nintendo or had some strong connections to the big N, therefore stuff like Simon Belmont, PAC-MAN, Banjo & Kazooie, or Mega Man. Then again, his unique style makes him very iconic due to how distinct he looks compared to the rest of the Smash squad. But for the time being I'm going to say Sonic stays, Snake leaves.
If we wanted a 3rd party character that greatly clashes with the other Nintendo characters, I think that Cloud and/or Sephiroth do the job just right. Come to think of it, Sephiroth's inclusion would have worked fantastic even without Cloud, imo...