In my humble opinion, I like knights

Why? They have a high amount of hp and defense. I have 120 stam unbuffed and I can survive already :P And knight armor is sexy, especially the golden armor at level 75. They also can survive for quite long in the arena. When a random BP that is not 'heavily' equipped comes and Sonichands me, I can survive. Slash + Keenwheel + Keenwheel combo is okay in PvM
and PvP. Keenwheel has 3 hits, and every hit with a 2h weapon, it has a chance of swordcross (randomly activates when hitting with a 2h weapon. It is the same as holycross, except you don't cast it yourself), so you can deal lots of damage.