Personally, a switch. I bet you guys are pretty familiar with the sub mentality so I'll go into my thoughts about the dom aspect a bit more:
The exhilaration of being bested by your own physical superior is matched by coming out on top of someone who is capable of putting up a good fight against you, IMO. I used to date a girl who was stronger than average and down for some playing rough, but she was never a serious threat for me. Maybe she got me in a tight spot once or twice because I made a bad move or something, but I don't think she ever beat me without help. Still, overpowering her was a big turn on because it was still a struggle, and a good one at that. It was still muscle against muscle, strain and forces exerted between tensed bodies.
Now, if I'm with a conventionally attractive (weak) woman like I unfortunately am 99% of the time, I have no interest in dominating her... where's the fun in that, where's the struggle? I mean if I can resist all the force she can muster with her entire body with one hand, and effortlessly, almost always the case, where's the fun in that? So things are pretty vanilla in that situation, which is far too often. Most of those women are not interested in domination anyway, beyond some very tame aspects like being made to feel small or being surrounded. One girl I dated in high school used to like me to squeeze her hand until it hurt enough that she asked me to stop, but that's about it.