I wouldn't focus on Naz and Aldama specifically. Neither may be available (I think they both get resigned by their current teams), but my point is that I'd rather add two high end 4th and 5th starters (Santi and Naz are examples of those kind of players) than an aging star like KD. Any of them will require trading though, since there won't be FA's available to accomplish this. Trading for KD kind of locks you into having KD plus some cheap guys to fill out the roster. I'm happy with a big 3 of Wemby/Fox/Castle and surrounding them with a more well rounded roster.
I wonder how much more expensive it would be to go after TMIII than KD. There might be a team out there dumb enough to drive to cost of KD up to two FRPs. Could two FRPs + Vassell get TMIII? That seems on par with a Dejounte-like haul, but TMIII isn't at the level Dejounte was at when we traded him to ATL. If the price were the same, I'd rather have TMIII than KD, even though KD is the better player, because Trey's contract leaves us flexibility to fill out the rest of the roster.
At the end of the day, however, all of this requires us to move on from Devin and Keldon, so that's a win on it's own (although the post-ASB Keldon we've been getting would actually be quite valuable... but this is just Keldon on a heater, there is no way this is sustainable)