ski height schould be determined by weight/ability. Im 6'1 190lbs and i rock armada 181 ar5s. They are perfect for me, but ive also been skiing for 14 years. I know how to throw a beefy ski around no matter what shape/height it is.
See now ive also ski on 169,174, and 186.  The shorter skis are so much more manuverable, and just fast to spin. The long skis are soo stable during anything......but at the end of the day of pushing a 185+ ski around you get pretty tired if your not used to it. If you are under 140 lbs.....you just don't go over 180. Trust me.