How Much Freedom of Builds do you have for GM3?

[XCPTNL]

Short answer: it totally depends on your gear and the rolls on it.

That being said some stuff is a lot better than other but with proper builds everything can be solo'd on GM3 even though fighting bosses with Storm is always a pain in the * and also some builds are obviously better than others for this purpose. If you can solo the first room of Sunken Cell on GM3 you should be fine for everything else the game can throw at you currently.