I really don't see how any of the fighters listed would be title holders or champions now. Shavers could be cruiserweight champ, but his cardio and chin were so poor.

Ken Norton would get blasted by Vitali and he would do well vs Wlad because although Norton was strong and he used that strength vs Ali and Holmes, Wlad is just as strong if not stronger and has been known to bully his opponents into range.

The other guys were just not as consistent.

Ron Lyle may have had a shot vs a younger Wladimir who was more willing to trade, I see Ron Lyle being able to pull off a Brewster/Purrity type upset if there would be one person who could, but even then it would be quite a long shot.