Agree with this, Hayward+ for Wall would be a lateral move IMO (although if we're going to lose him for nothing in a year, we'd be lucky to get a talent such as Wall in return). I don't know if WAS would be interested but I would definitely trade Exum/Burks/picks for Wall. With Hayward only having one more guaranteed year on his contract, we need to either trade him or add high-end talent around him.
Wall/Mack/Neto
Hood/?/Johnson
Hayward/Ingles
Favors/Lyles
Gobert/Whithey
I doubt WAS trades him (especially in a deal centered around a player coming off a serious injury), but that roster (with the right addition or 2) could be a serious contender & potentially convince Hayward to re-sign at a reasonable price as well as keep Wall reasonably content. As someone mentioned, due diligence on Wall would need to be done prior to any trade though.