Spike.
I wonder if he could make a healthy relationship work (I don't call what he and Drusilla had healthy, even though it lasted for over a century), but he is too interesting to not want to date.
And even though I can't say I like Angel as a person, actually I think he needs to get his butt kicked, a lot (I thought so before season 8), I do think he would be very pleasant to date. Open doors, pay for everything, be a good listener, "make love" (not just have sex, but I think he would actually "make love", as in being gentle, playing music, candle lights, not ask for anything kinky, you know. Of course, that would get dull after a while).
So I guess I want to date Spike, but I want Angel to be in love with me, and be "the friend" that I go to to whine about my bad boy boyfriend.