My biggest concern with keeping DeMar is what his next contract will be. In 2016 the salary cap will go from $63M to an estimated $89M. DeMar has a player option that he will most likely exercise so that he can get in on the fun. The problem is many teams will have cap space that year and most will be able to afford paying DeMar his maximum.
DeMar's maximum will be about $24M. If someone offered DeMar $20M would you want him back at that amount? He'd be a UFA, but let's assume he'd give the Raptors the opportunity to match.
At what value would you say he's not worth keeping?
Note: Currently DeMar makes $9.5M which is 15% of the cap. 15% of $89M is $13.3M.