Add to the mix that you outleveled your quests already and are fighting mobs 3 or 4 levels higher than you. Then go alone without a companion in any lvl 27 zone, dont pot and see what happens.... against groups of mobs you will be fighting for your life. Even with all you skills off refresh a mob of 4 enemies poses a…
I don't think playing to lvl 20 or so is an indication of a OP class. Its too early to tell plus survivability is an issue especially in instances from what I could tell at 28, was chugging health pots to stay over half HP.