Biggest MMA hypotheticals?

Got talking to a colleague about guys who's careers ended too soon, never got out in their prime, etc. Amagov was the one that immediately came to mind for me. The man was a machine and so fun to watch.

Another big what if fighter was Lee Murray. I don't know how far he would have gone, but getting a proper run from him could have made the MMA landscape so different. Not sure if that would be for the better or worse, but imagine an actual sanctioned fight with him and Tito