Gorgons are amazing

Look for gods and items that boost damage% an resistances. You are a regenfighter so blackspace is very important, don't waste it. SMM will be easy, for the Goo set up some dings and maybe use potions for the kills. If you don't have enough firepower to bring it down, try to raise your deathgaze high enough that you can hit through his resistances. That will make it regenfightable, but fireballing is still an easier solution.
Edit: On HB you don't have to kill the Troll while being lower level if you choose to fight it. You can push/move him out of the way, and come back to him later when you overleveled him, so the kill is easier and you still get the awesome CP bonus.