I'll have to look, but I think the SAC first and Memphis first were held out. But even if that isn't the case, you're looking at 14, 20 and 22 from last year and 14 from this year as being the best-case scenario. That would've given the Spurs four firsts last year, with their own pick probably being the best since they would've probably missed the playoffs comfortably without DMDR.
But that highlights the issue that plagues/bogs down most tanking teams. If you play the game for maximal future value, you end up with a bunch of meh or average young players that you're reluctant to get rid of because you don't know which of them are worth holding onto. Having six first-rounders in two years is just too much. Boston has had to piss away picks for multiple years now. Unless you're getting the right picks back, I don't think the value is there.