This is what i thought, before exping my thauma to rank 20.
It can be a great DRK too, inside an 8 men party. You can focus on debuffs and thaumatuges can do magic damages.
The worst thing of Marauder is accuracy. I realized that with Absorb ACC, Hawk's Eye, Still Precision and Keen Flurry, you can easily take you DEX down and raise your PIE up.
It's all about finding the best way to merge physical damages and magic accuracy. I don't want to heal myself or do magic damages, but i want to debuff the mob and take away work from mages if needed. Then with Invigorate i can always have TP for enetering Battle Regimens.
It's pretty cool, and it's different from the standard! So fuck yea to DRK! XD