Ramateshkol’s on target.
I hate labeling and pigeon holing, but chances are the girls who are interested in boys who aren’t in full time learning want someone who has a clear idea of what he wants to do. OTOH, if you have a reputation as being consistent, smart, and a mensch, who does plan to finish school, then you shouldn’t have a problem. (Hey, going back to Musical Chairs, boys don’t have problems, right?)
And yes, people do reinvent themselves, go for advanced degrees or change direction in midlife (or close to it) but many of the people I know who did that did have some degrees and solid experience in their fields already.
And I’m all for having a plan, I think it’s good for all boys. Nothing needs to be etched in stone, just some good hard thinking and self knowledge. Check out Rabbi Horowitz’s article The Plan and Mr. Irwin Benjamin’s on the same (it was in Hamodia, probably googleable.)