My take on the weight issue, is that his weight is what is preventing him from becoming a good starter instead of a good bench role player.
If his weight is better, and he can play 36 minutes per night and move well enough to play solid team defense, we would have ourselves a nice sub all star, and next summer he would be worth at least 12 million per year in an extension.
But if he cant lose the weight and remains a nice bench scorer, who is an injury risk with the weight he wont be worth more than the MLE.
This coming year is his proving ground for a contract extension. If getting better, and money doesn't motivate him, nothing will.