The Spurs have done a way better job than Ainge in finding cheapie role players to surround their Big 3.
Splitter, drafted 27th in 2007. If the Spurs take Alindo Tucker instead, as Ainge did with Giddens instead of DeAndre Jordan, they don't have a competent big to play next to Duncan. Or if Ainge took Marc Gasol instead of Pruitt at 32 in 2007.
Danny Green, $800k FA, starting for what will be a Finals team. Ainge hasn't had a solid hit on a cheapie FA since PJ Brown's four months as a Celtic. Green averages 10.5 ppg shooting 45/43/85% and plays solid defense.
Gary Neal, same as Green. 40% 3 point shooter who plays gritty defense.
Matt Bonner. $3m salary. Three point specialist the past 6 seasons who stretches the floor to create room for Duncan and driving lanes for Manu and Parker. Ainge's $3m signing, Chris Wilcox, can't stay on the floor due to injury (and his unforseen heart condition)
Kawhi Leonard 16th pick of the 2011 draft. Spurs spin George Hill, who they picked 28th in 2008, for their only pick above 20 since Duncan in 1997, and they hit a home run with Leonard. Ainge's bounty in 2008, the aforementioned Giddens two picks after Hill, was nothing but salary filler when dumped two years later. BTW, Pekovic, Jordan, and Asik were all picked after Giddens (as was Chalmers, Dragic and Mbah a Moute). Any one of those bigs instead of Giddens and the Cs probably have at least one more title. Unlike head case Avery Bradley, Leonard is right sized for his position and doesn't wilt in the playoffs.
Blair, picked 37th in 2009. Ainge hasn't drafted a player besides AB who has contributed around his Big 3 since BBD in 2007 (and I know that BBD was picked by Seattle, for Ainge). And AB's contribution was minimal due to his many injuries.
Boston's FA acquisitions (Shaq, Sheed, JO, Lee, Jet) all didn't work out while SA's cheapie FAs did. Using hindsight, if Ainge picked a big in 2007, then surrounded his Big 3 with cheapie young role player show could shoot threes and defend, like Green and Neal, the Cs could be where the Spurs are, if the Cs stayed healthy of course.