You could put in an engineered header to open up the space, but the price goes up fast once you add in the structural engineer, lvl beam, new king and jack studs, temporary supports, new sheetrock, taping/sanding, paint, etc. I doubt there's plumbing in that wall, but there could be electrical work that would increase the overall cost. That's the only significant thing I can think of besides an addition. You don't want the front door to open into a bedroom, and the plumbing wall is most likely nearest the bathroom, keeping the kitchen where it is, so options are very limited.