The San Antonio Spurs were the number one defensive team in the league and won 61 games, so this postseason does not define their season or their future. The Spurs were rattled and dampened by injuries of two key offensive players. Parker was still probing the paint at his age and Kawhi Leonard was a bonafide scorer, no team could survive losing these players. Spurs' system is still a system that can win an NBA championship, the team was not derailed by themselves but by unfortunate circumstances.
2) Young Pieces:
The Spurs have players that are rising and could benefit greatly from summer workouts. Jonathan Simmons for one had a great playoff season but can improve the consistency of his long range jumper. The Spurs also have Dejounte Murray that needs to hit the weight room and work on his jumper overall as well. These players have speed and athleticism that the team desperately needs.
1) Best Player in the League:
The Spurs despite what changes they may go through still have the best player on both sides of the floor in the entire association. Leonard improved so much offensively this past season and the Spurs can expect him to continue to grow. The next step of his evolution is to make the the players around him better--increasing assists numbers. The Spurs would have likely beat the Warriors if Leonard was healthy so as long as they have him they will contend.