LEST POST DREAM-ROSTERS. On a 30-round characters:
Capcom:
Ryu (Street Fighter)
Dudley (Street Fighter III)
Laura (Street Fighter V)
Karin (Street Fighter Alpha 3)
Megaman X (MMX)
Edward Falcon (Power Stone)
Phoenix Wright (Ace Attorney)
Hayato (Star Gladiator/Plasma Sword)
Arthur (Ghouls and Ghosts)
Firebrand (Demon's Crest)
Mike Haggar (Final Fight)
Gunloc (Saturday Night Slam Masters)
Guy (Final Fight)
Tiffany (Rival Schools/Project Justice)
Hauzer (Red Earth)
Marvel
Spider-Man (Miles Morales alt, plz)
Doctor Octopus
Squirrel Girl
Luke Cage
Daredevil
Doctor Strange
Human Torch
Wolverine
Juggernaut
Doctor Doom
Captain America
Iron Man
Arsenic and Old Lace
Rocket Raccoon
Shuma Gorath
My dream roster of thirty total would NEVER happen because it leaves out too many IPs on both sides (DMC, Resident Evil, quite a few Avengers), but that's what I would want ideally.