Hayes a blown up Cruiser himself. He was found out big time against Klitschko at Heavyweight. Wins against the likes of Monty Barrett and an over the hill Ruiz look great on paper but only tell half the story. I'd go out on a limb here and say the Bellew of now would have beaten most if not all those who Haye beat at Heavyweight (Valuev being the question mark - but only because of size). That being said the Haye which reigned at Cruiser would probably beat Bellew.
Father Time caught up with Haye, like it did with Hatton on his comeback. 6 years at that age without a meaningful fight is just too much. Got to give credit to Bellew though, doubt Haye expected him to move as quickly as he did, even before the injury he was swinging and missing wildly. It's incredibly difficult to adjust, especially if you haven't fought anyone in that mould for the best part of a decade (Enzo Mac the last in my book).
Thing which impressed me most about Bellew was his ability to take Hayes big punches. Shot or not the last thing to go on a boxer is their power, Haye still carries serious ammo in them gloves. Fair to say when Stevenson beat Bellew at Light Heavy he was seriously weight drained, it's actually quite scary looking at how skinny he was for that fight. The extra timber does him the world of good.