I still see Supes winning majority in all these. Xavier would be tough, but I think Supes can muster his will to fight off his attack at least a slim majority of the time. Also his speed could help him attack before Xavier brings his mental might to bear (Supes isn't faster than thought, but he can attack so fast Xavier won't even have turned his attention to him;that's where prep makes a difference).
Supes would beat IM a huge majority, but it will always be a good fight.
Strange could, on occasion, defeat Supes with what appears to be embarrassing ease if he gets off just the right attack. But I think Supes will still beat him a majority of the time as he is more of a fighter.

> Supes has his specific weaknesses against Mental/Magical/Energy attacks...