Which class for solo play?

In the meantime some have played all classes and got an impression.
I realize that a lot has not yet been approved and a lot can be changed.
But at the current state;
Which class is good for the solo game, so that you do not lie on the ground immediately when it is a stronger Mob.

I was able to solo greyfang mini boss from drakwald forest at lvl 21 with my warrior priest tank. It took a while and some potions tho.