How about fighters at his own weight? Walker would have chances against anybody. What makes you so sure that he wouldn't have chances against them? What makes him so inferior to them? Cool, but you were talking that he had too slow feet.
1. Cruisers like Evander and Haye would beat him. 2. He's less skilled. 3. You might make a case for him being faster, but they seem pretty close
So he'd be champion-level fighter who would lose against the best of the best? Break it down though. Walker is incredible body puncher and his ability to pressure his (often much bigger) opponent is nothing sort of incredible. He had arguably the best hooks ever. Sure, he couldn't dance like Robinson or box like Hagler, but he had other specific aspects of his fighting in which he was much better than him. I'm not saying he would beat any of them, but he was a terror for any opponent. It's not close between him and Foreman. Or Bowe for that matter.