Giorno totally wouldn't be awkward with Part 3 Dio floating around... And especially if you-know-who's spirit is still inside Coco Jumbo. Yeah.

I was initially thinking of making Hol Horse because... Well, he's Hol Horse. 'nuff said lol.

I think Diavolo's a bit too much, given that he can basically say screw-all to all the damage dealt to him (because King Crimson. It just works.) Dunno about Giorno once he grabs GER, either. At that point, Giorno can basically do the same thing that Diavolo can do, except with more applications and the probable retention of Gold Experience's life-giving abilities. In other words, insanely strong combat medics who can negate damage. Ow.

(Not to mention GER basically puts Giorno on god-mode status, becoming nigh-untouchable and making all damage moot.)