Definitely Raichu. Pikachu with moar range, moar power, and moar TUNDAPUNCH!!!!!!!!!! For those who don't know, Storm made a winsauce Moveset for Raichu at my request some time ago. =D
It's gotta be Udagawa's back streets, bro. If TWEWY somehow got into Brawl, it wouldn't be right to ditch the CAT mural. Some Taboo noise to spice things up wouldn't be a bad idea either.