I've been using a close-set chip breaker for a couple years. It does indeed mitigate tear out, regardless of the bevel angle, and I have not found that it affects the finish quality of the surface at all.

I've never been one to mess around with the frog.

I will say that the most dramatic improvements in my planing quality have come from 1) improving my sharpening, and 2) learning how to read grain direction. If I were to start again, I would focus on these two things for years before looking to altered angles.

All this assumes of course that you have a properly set up plane; namely that your sole, breaker, and blade are all flat and true at the business ends.