Five minute rush job with the gear on hand:
Warriors, especially non Anathema, one-hit-wonders aren't really comparable to what Rangers do the majority of the game. They only creep up near the end of the game and even then are still worse off.
My only point is that even if Warriors can eventually one-shot bosses, it's not exclusive to them, and they also start doing it later than the other physical builds. People sure love to fixate on Two-Handed Warriors for some reason though.
Non Summoner Mages on the other hand are at the bottom of the barrel all the way through.