Frost-- Plays like a faster more rushdown focused sub-zero, with no projectiles, instead the last hit of a few of her strings will freeze opponents allowing for hit confirms.
Robot smoke-- I don't really how he plays, just let him be in.
Tremer-- don't really like him personally but everyone else wants him in. Have him be a "charge" character, slow and powerful, with lots of super armor.
Bo Rai Cho-- Change him completely, make him a grappler style character, but aesthetically make his moves similar looking to a mix of Kung Laos and Liu Kangs, fire balls and spinning and maybe a dive kick. No farting, but has a puke fatality.
Reiko-- Make him a playable balanced shao khan, hammer and all.
Tanya-- Black chicks are hot.
Goro-- Playable and balanced, completely overhaul him, remove his fireballs, make him a slow grappler type character.
Scorpions wife-- QC reanimates her after scorpion has a hissy fit, she comes back under quans control.
Another one of reptiles lizard people-- Make reptile more human, and have this one go full lizard tail and all.
Mavado-- No hooks swords, but focus on his grappling hooks, not sure how to make that work with out ripping off spencer, but eh.
Also two other brand new characters, along with the 2 I suggested it would be 4 new comers. Would also like a slight revamp to cyber-sub, remove his bombs maybe and give him something more interesting. And a alt costume for Ermac that looks like kitanas real dad.