Bards are certainly the most annoying, though Mist Veil (I believe that's what it's called, the skill that reduces someone's range. SMN has it, no idea which other classes/jobs can use it) is a fun thing to use with that :P

I myself main a DRG and started Frontlines with that, but SMN is infinitely more fun, since I won't have to chase after every single person ever and I can just pop on some dots and wait for someone to die.
Melee classes have always had issues in any pvp from my experience regarding ranged classes (not enough ways to break the gap etc.), so I'm interested what Ninja will bring to the table in a few months time.