Warriors tend to be one of the hardest classes to rank after a certain level. Transmuters, bards, healers, paladins, goodie conjurers once they all have an arcon on the other hand should have no problem rounding up a successful group. Of those four, I'd really only call the paladin a man-at-arms type class.

If your talking the lower levels, then yeah as has already been pointed out, there already are several quests that give experience. That help get past the rough spots for weaker classes. With a little bit of luck and poking around you can find quests that give anywhere from a few hundred to a few thousand experience a pop.