Kidd is a pretty good defender and a trio of him, Dirk and Howard, with Diop and Dampier to protect the rim is pretty formidable. Harris and Terry telegraph their passes and they don't create good shot opportunities for their teammates. Kidd is a huge upgrade over either of them. Only problem with Terry gone is that now you need an outside shooter, but we can probably get a Steve Kerr type for the MLE. As for Dirk and Nash together, they are both a lot better than when they played together. The Mavs also didn't have any interior defense whatsoever to speak of when Nash was here.
Even if we left the team alone, I would be fine with that. Phoenix is going to shake things up for financial reasons and it's premature to say that the Warriors are back to being perennial playoff contenders. They have a number of FA's and Nellie may not come back. The Spurs however are going to be there every year and we match up to you guys in the same way that the Warriors match up to us. I'd rather construct a roster to beat San Antonio (which is what we did) as opposed to blowing things up so we can beat a team like Golden State.