Could be that few women voted in this poll and they all selected human female...
Well, not all of us. I'm playing a female dwarf on my first run. (Varric romance would be a nice bonus, but I'll play female dwarf first even if he's suddenly got Iron Bull fever and will only date male qunari.)
I have two reasons for this decision:
1) Dragon Age dwarves are amazing. Their origin stories were my favourites in DAO, and I love the lore surrounding them.
2) I find it easier to identify with them than the other races, on a physical level. If I were a foot shorter, I'd blend right in around Orzammar. On the other hand, I look nothing like any female human I've ever been able to play in a video game. (Or the elves, either. Needless to say, I am also not a seven-foot-tall horned giantess, although that sounds like fun.)