Hmm, good question. Mostly I think it's very easy for dwarves to be boring. The basic dwarven "template" is very generic: short, bearded, gruff, alcoholic. Not a lot of character development past a few posts. As with any other race it's easy the break the mold (I could easily make a nervous young dwarven sorceress that's self-conscious because women of other races don't have beards) but mostly that requires a preexisting interest in playing a dwarf. I love the little mountain men, but let's face it, when people read about elves everyone has a different character concept in mind. When people read about dwarves the first thing that pops into everyone's head is functionally identical to Gimli.