You serious?
If a basketball team says they have trouble with size you don't tell the players to grow, you pack the paint with your biggest players and dish it inside. If O'Tools says he has a problem with reach, Hamiti should favor positions that take advantage of his length. Adjust stance and ties to make it harder to get at legs, gets arms out first from bottom, de-compactify body position when O'Toole forces scrambles, look for cradles, and so on. How you possibly concluded that Hamiti should grow his arms longer is beyond me.