Serious talk: If your DM steps up his game, you'll NEED Power Attack. If he doesn't ... well, problems ensue one way or the other. I would take Power Attack (along with Reckless Abandon on 4) and start RPing the fights. I would start gloating over how you don't even have to put real effort into your swings. Stop using Rage in every combat. Don't be an ass about it, too. I guess your DM gets the hint. Generally I always feel that taking feats for fluff purposes is kind of weird. DownPLAYING your character on the other side is not.

The combat sounds like your DM is shy in fear of killing anyone, so your mettle isn't tested.