Attractiveness is in the eye of the beholder, so what I find attractive (or not) isn’t necessarily what someone else might find attractive … and that’s okay.
I tend not to picture characters when I read.
I’m more interested in their personality and especially in how they treat other people (okay, other characters).
I consider an attractive romance hero to be one who is intelligent, hardworking, and puts the needs of others before himself (especially the needs of the heroine). He should be a Christian (well, I mostly read Christian romance so that should be a given), who is loving and caring and unselfish, who doesn’t get angry without good cause, and who is never abusive in any way.