My Mustang is 14.2, maybe 14.3 on a good day, and I am 5' 6" and weigh 200 lbs. (actually, I was a bit heavier in this photo).
He carries me great, but he is built like a tank too. I think the build of the horse is more important than it's height, unless you are a very tall person. Me, I worry about good bone and feet on a horse more than height.