Usually that kind of move is a bridge to nowhere (see your Payton and Wilkins examples), so let's hope it doesn't happen. Also Ainge just burned Brooklyn by trading them his aging stars, I hope he's not going to turn around and overpay for someone else's.
It will be tough to nab a free agent that way, since most about-to-be-washed up stars seem more content to go ring chasing now if they're a free agent, though I guess Derrick Rose and Joakim Noah could be possibilities. Noah will be free agent in 2016 at age 30, Rose in 2017 at age 28, and with those guy injuries lately (and decline in Noah's game), it will be interesting to see what the market is for those guys. They might still have something left to prove and could want one more big contract before they go the ring chasing route, and Chicago might not want to re-up with them at the price they're looking for. You could get them either as a free agent or trade depending on what's going on in Chicago.
From a trade perspective, how about Chris Bosh if Miami needs to blow it up in a couple of years?