It was, I believe, Satan who decreed that all coach seats be the same. Why not make all clothing the same size as well!
The only rational solution is to classify pax by height. Have two or three zones - one meeting the current standard, and the others bigger.
I am 6'-3 and 235 lb. And yes, the 12 hours SFO-ICN on United did make me want to sue someone. Must be my dang american DNA....