I think the need for Hawkins to vastly improve his outside shot is a bit over-blown. Houston was daring him to shoot, but he was on the court with DMW, Kofi, and Curbelo quite a bit in that game. None of those dudes wanted to shoot. If he is out there with some combination of RJ, Goode, Podz, TSJ, & freshman PG to be named the ball will find a shooter before the defense can recover from the Kofi double/triple team.
That said, if he wants to get to the NBA the three is absolutely imperative. I think he can be an effective player at this level w/o making a huge leap outside.