Either way, it's silly to speak on this in absolutes like how you said "However, you never hear of a shooter Turning aggressive for some reason, and driving more" You obviously didnt look into that at all as you can find examples of "shooters" expanding their game to include increasing their free throw rate.
I think it will be pretty difficult for him to not increase his FTR rate (as it was really low last year, even compared to his first two years) this year due to the simple fact that he will be asked to playmake more, for himself and others, which will probably lead to more varied plays being ran for him. If I had to guess, I would put his FTR somewhere between .22 and .24 for this upcoming year. That still isnt good, but it would be an improvement.