Comments are for something posted like pictures or videos etc (maybe in youtube)..Here we call it post instead on comments
There are only 3 class, calling one of them OP (over-powered) would mean "the best" amongst the three, because if its not the best then the term OP would lose its meaning. I don't know how it is in you, but IMO asking a question and being rude to other forummers don't go along each other.

Now to answer your question, Tank are really OP at L16 specially with the arcane mallet, pet-animancy and awakening. Tanks can do massive damage and be tanky at the same time.
If youre only going to play for fun, then Tank would be a boring choice (since its OP) the Sorcerer would be challenging and Rogues would be (nah don't use rogue). If you can buy Para/Syri gears then rogue will be worth it. Still tanks would be the best choice if you want to dominate.