Dance, because of smooth forms, happy happy joy joy personality and the artistic feel to it. Wouldn't go out with a Hulk-ish type myself. :/
They both got lots of grace and both can be wild. I see martial arts as more of a collected individual, while I'm not a fan of "happy happy joy joy" personality. Well, not much against it, but wouldn't see myeslf with that
I think I have more with dance, if only because he/she would use the graciousness in other situations than life-threatening. Martial artists tend not to go all-out unless threatened, while dancers perform at fullest graciousness for the entertainment of others