My greatest wish would be Gnolls, but I know that isn’t going to happen. So my next priority would be goblinoids - goblins, hobs, and bugbears. I know we have them in Monsters of the Multiverse, but with the changes the monster versions of those species got in the 2024 Monster Manual, I want new PC versions with similar changes. A bonus to damage on attacks with advantage for goblins instead of Fury of the Small; the ability to move a grappled target without spending extra movement for bugbears instead of Ambusher; hobgoblins are ok as-is, I guess.