The additional 6-ppg scoring boost this year has been very encouraging, not to mention the improved FG%. They are hitting .486 of their shots, #2 behind PHX at .496. As the schedule gets tougher, it will be interesting to see how well this holds up.
Points Diff. via a high PPG and FG% can be fools gold come playoff time so if the Spurs hope to carry through to the NBA Finals, they will need to make improvements in their interior defense. When taking a statistical view, as you have done, then Opp. FG%, Opp. APG, and Opp. PPG need to drop in order to make a difference in May and June.
Major concerns. Long teams, teams with height and length and teams with good outside shooting.