This came up in a chat I had the other day and I thought I'd ask here. For those of you who play both sides of the fence in more ways than one ;-) I was just curious, are there certain combinations that don't appeal to you in terms of combining gender with Dom/sub? Meaning:

A Dominant, other sex partner.
A Dominant, same sex partner.
A submissive, other sex partner.
A submissive, same sex partner.

Do all four appeal to you or are there some that do not? I was talking with a bisexual girl the other day who said she enjoyed submitting to men but liked her women more vanilla, and I was curious how others felt on this.