To be honest, i was a bit dissapointed too with the 2H axes, the increase in damage is a bit low while loosing attack speed, walking speed and the ability to carry a shield... BUT the 2H iron hammer is for me one of the best weapons in game. There's no way i'll go into the swamps without it, and when playing in team, i still use it in the plains. I wish they'd add a cristal 2H hammer, cause i really like the looks of the cristal axe.
Still gonna try using the 2h axe and see if it can be viable with higher skill levels.