Should I ditch my mage?

Well I just learned that Archmages are useless for bossing, and that it will be pretty much impossible for me to get into any boss run that is higher than Papulautus (and probably not even pap). I really want to boss (that has been my main motivation for training) when I get to 100. But now it seems that since I am interested in bossing, I've pretty much hit a dead end. So I am STRONGLY considering quitting my mage and making a gunslinger instead.

What do you guys think?