I really wish I knew what the big deal with Sea Raiders was, lol. I usually go straigh from river pirites to fighting them. I find them easier that any of the others. I voted for black khergits, but that mainly because I usually play foot, so, that for an obvious reason.
As for Sea Raiders though, I find that they raely ever hit you if you simple sidestep.
Actually I was 2 shot by river pirites once, foggy night map, was finalling off the last of the 3 that rushed me. Two of them hit me in the head with rocks for 20+ each. Should have bought a helmet....lol.