If dominant means able to take the lead or initiative at times, and things like knowing what she wants and more prone to communicate about it, without the bossy attitude and stuff, I'd go for a dominant woman definitely. I'd love the clarity in what she likes/wants. (If also dominant in bed, would be a very nice change of spice from my only past experiences being dead starfish in bed. I'll tell you that is about the biggest turn-off there is to me.)
It would be the best of both worlds if I could sometimes be the dominant one as well - as taking the lead when it's clear what both parties want can be great fun as well - but I don't know if you would consider that requiring a woman who's not only dominant but somewhere in between. (Oh man, "wrestling" for sexual dominance when in the bedroom would be tonnes of fun I bet.)
Between the two I'd choose submissive. I find it more attractive. Also when I see girls who have a shy or submissive demenor I just really want to cuddle with them. They're so cute and innoscent, you just want to hold them and make them feel safe.
I'm a dominant personality so if girls were constantly clashing with me, it would trigger my anger and that is bad for everyone. I like strong-willed girls but I will be the dominant personality in the relationship.