uber mega fun fact
prior to the update that added support for Wave 3,
it was discovered (twitter.com) that Mario, Peach, and all of their variants (not counting their baby counterparts, in any case) no longer appeared as CPU rivals; this has since been reverted. since drivers who are selected from a sub-list, such as female Villager, the non-green Yoshis, and some Inklings, never appear as rivals, we can take this untimely removal
to be a clue (twitter.com) that the devs are experimenting with integrating clone characters into their respective original character's slot in order to free up some space on the driver list.
yep. that means new characters might be coming. and, since the sublists should already be there for Mario and Peach, who's to say we aren't looking at additional costumes for existing characters, too?
Four variants were removed from the rival list, namely Tanooki Mario, Cat Peach, Metal Mario, and Gold Peach. with four new empty slots, and if what i said above ends up being true, we can expect 4 new characters to be added. place your bets!
diddy kong, funky kong, pauline, birdo