Okay well as far as ive seen and ive tested, Mages are the stongest class with the correct build. I know some of you may argue with this statement but its true they can hit well over 60k. Mages as well as archors start off kinda weak and arnt best for pvp until about 40+ both of these classes get strong at 30 though.
Warriors and kff are very strong classes but they do end up not very useful with some quests like kuito temple mages are best for them anyways back to my point, these classes are perfect from lv1-55. Warriors are heavy hitters and can do many things better then other classes.
kffs are very stong sabre isnt one of my favorites or sword, i like bare hand more becuase they can hit 10k and a lot higher but i havent seen one hit as high as a mage fully epic potioned, On my bare hand i did everything i could to bring up his melee it was 9483 without potions and skills after them in battle i hit about 19-21k and this isnt enough to kill a tank build its very strong though. Kffs are very strong all the way through what ever weapon you use though.
Shamons are the best when you hit lv55 because you can be any build really but most shamons end up being axe or mage, ive seen some archors and one bare hand. Shamon skills are good for any build though ive never had a lv55 shamon but im working on it.
This is what i like to call the circle of power(lol) every class is stronger then another but there is always a srtonger on so its not about what class you pick its about what build you pick,its that just some classes can do some builds better then others.