I built my first glass backed recurve in shop class when I was a freshman in high school (1967 I think). It was supposed to be 45#, it's pretty close to that. I still have it and it still shoots pretty well. Of the dozen or so that were built, I think mine is the only survivor.
I graduated to a Herter's Model Perfection 50# in 1974. My eldest son now owns that one. I shoot 45-55# bows. I guess I haven't changed. I never felt the need for anything heavier, and don't feel the need to go any lighter at this point.