There is no way Thanos is going to win against WWH in a fist fight. He was holding back (according to the WBH arc) and still messed Hercules up in a few blows. Now Herc damaged WWH well too so it proves Thanos can do the same and make this a fight. IMO, I see Thanos about as strong as Hercules but a tiny bit more durable to physical blows. Heroes hold back and villains don't. That is why it sometimes appears that villains are stronger when they are really not. Allow the hero to let loose and clearly they are stronger or just as strong as the villain.
Now against Savage Hulk it depends on the power level. Savage Hulk is very variable but at best shown will shit on Thanos in a fist fight. An average Savage Hulk will be a good fight but may lose a slight majority.