Right now I'm playing GLD and I'm not stopping until 50 (only 3 levels to go.. woot)...

After that, I'm probably doing marauder because I can reuse alot of my GLD gear for it.

Though PUG and LNC are fun as heck too.. never know..

All that said, I'd suggest MRD since that combined with GLD is the prerequisite for Paladin.