It's hard to say, after watching how Big Al has developed, that another team could have made a better offer. Minnesota got cap space, a star big man, and two part-time starters / rotations players. That's a good haul.
No doubt, Golden State could have made a good package around Biedrins and/or Ellis; that package looked better at the time than it does now, of course. As for Dallas, they couldn't have given Minnesota the young big man they needed.