2. Dylan Cease
Yes, yes we all know that the Cubs should not have made that Jose Quintana trade - which can now be safely regarded as the Dylan Cease trade in my opinion. But hindsight is 20-20, and there was never a guarantee that Dylan Cease would end up being this good. But after a 2nd place finish in Cy Young voting last year after compiling an almost unbelievable 227 strikeouts over 184 innings, Cease has emerged as one of the best pitchers in the game. And the Cubs should go after him and bring him back to the north side.
The question is will the White Sox be willing to blow it up this year or next year? Their core is getting older and their pitching staff is in shambles outside of Cease and Mike Clevinger (on a 1-year deal). Time is ticking for the White Sox to either start playing better or face the reality that their team is just not good enough for a deep playoff run. Trading Cease would not be out of character either since the last high-level ace the White Sox had (Chris Sale) was traded to spawn a rebuild.
The Cubs need an ace like Cease, and the White Sox need prospects like Brennan Davis or Cade Horton to jump-start their rebuild. This trade is unlikely to happen this season, as Cease still has two more seasons of control on his contract. But I predict that the White Sox will trade him sooner or later and the Cubs need to be in on the sweepstakes.