chicago is going to fall apart next season since they are loaded with old players.
There's no reason to have a "rebuilding" year in MLS. You can go from shit to pretty good in an off-season really easily (see: Fire, Chicago), so why punt a whole season just because you get rid of a couple of players? The pool of potential impact players in MLS, globally, is enormous.
Also, dont think its a good idea to constantly rebuild with old players.