Personally, I kinda hope they don't make the mistake of going overboard and suddenly putting Wart in everything possible. Really, he was a good boss. He needs appreciation. But let's hope he doesn't suddenly get the sort of appreciation Petey's been getting. Petey was cool ... then they overused him.
Although, I wouldn't mind if they put in Wart if it's instead of putting in Toad. Then it'd be A-OK! Of course, if they put in Wart and don't put in Waluigi, I'd be very bitter. For lack of better wording.
EDIT: Hey! I just had a cool idea! They should put in Mouser! ... Or at least a Mouser trophy.