I really am hoping that Ants trades ACab this offseason just due to the fact that I think he would net the most in return and net the most ready MLB players. Living in St. Louis there is a lot of chatter right now about the Cardinals interest in him and they are very deep in their farm system. I would not mind seeing something like this:
Seth Blair SP
Matt Carpenter Util
Matt Adams 1B
Adams is ready to play in the league at 1B and would be a very good power bat in this lineup. Blair is possibly 1 to 2 years away from contributing but I don't see the Cardinals parting with their stup P prospects in Rosenthal, Miller or Martinez and I don't see Lynn or Kelly being anything more than a #4 starter in the AL. Blair has the best upside of probably the non untouchables in their organization. Carpenter would be a great addition too as his bat is lively and if they do get rid of Choo they can stick Carps in RF at times while also DH'ing him on other days.
This leaves Aviles starting at SS which I would not have a problem with next year while waiting for Walters, Diaz or Lindor in the next couple years. Also then they could possibly still look at moving Choo for LF/DH help or sign Youk for DH help and use Choo for LF/SP help. I would hold onto Masterson right now and CP probably would bring nothing back in return besides a prospect that would be a couple years off.