What's funny is how academic this becomes in a few years ... my husband and I are 11 years apart.
My son just told me that he just hooked up this past weekend with a woman who was 11 years older than him ...
So I don't consider 4 years a big age difference.
The other stuff you have to work out for yourself ... it's a question men have been wrestling with since then started asking their potential mates out instead of clubbing them over the heads ....