I see him getting the Max next summer. But Max or no Max, the Spurs will still get extra cap room by waiting.
Even at the Max, Kawhi would be paid FMV under bump in the Salary Cap to over 90 mil. Just look at Parker.
I would say Kawhi has as much value to the Spurs now as Parker did the past 5 years. Parker was paid 12.5 mil a year. That salary is equivalent of 21.5% of the avg. Salary Cap. Let's say the Cap bump ups to 90+ mil, which is projected for the 2016-2017 season. At 15-18 mil a year, that would put Kawhi's percentage of Salary at 16-18% of the Cap. As you can see, that still would be less than the value of the Parker's contract at 12.5 mil.
Kawhi is probably the best perimeter defender in the league, well, I would say tied with James as this point. His offense has improved each year as well. At a Rookie Max contract, he is worth it considering the Salary Cap bump that is coming in 2016. Kawhi is entering the prime of his career, not the twilight at this point.