Which stroke easiest to learn, which easiest to swim WELL?

Do you agree that the stroke that was the easiest (or first) for you to learn may well not be the stroke that you eventually swim the best? So which stroke was the easiest for you learn? Which do you find easiest to swim to near perfection? I learned breaststroke the first but have never worked on improving it--unlike the other strokes, it doesn't seem to be so complicated. Freestyle seems to have infinite room for improvement?