I gotta say, Liston-Bonavena is the only one of those listed where I'd be curious about the outcome. Make all these guys closer to their primes, and we have some really interesting matchups.
Surprised no one mentioned Quarry-Bonavena. That fight was on tap a few times but something always prevented it. Liston wouldnt have fought Bonavena in a million years in the late 60s. No way no how. Liston was turning fights left and right with guys on the same level or worse than Oscar who didnt pose anywhere near the stylistic nightmares Bonavena did. A Bonavena fight would have been a long, hard fight for Liston and he woulda taken his share of punishment. He didnt want that.
Paul Williams vs Pavlik is one for me. Would PWill’s chin hold up well enough for his activity to overwhelm Pavlik over 12. PWill vs Canelo would’ve been a good fight too. Same question. Would Williams’s chin hold up to secure the decision.
I don't know if its been mentioned but Tyson vs Foreman was in the works in the late 90's would've loved to see it.