I think the Reds might be one of the favorites to take it all this year, depending on the pen and how Chapman does as a starter. The Cardinals will have a tougher time without Carpenter, but they are still capable of making a run. Neither team has the Astros to pound on and build their record anymore, but can still do damage.
As far as our division goes, the Tigers will still be tough. They get Martinez back, but I think they might miss Young's bat more than they think, even if they won't miss his glove one bit. Nothing changes until we figure out how to beat those guys. KC might be tougher now that they finally have some starting pitching, but I'll believe it when I see it. Cleveland set themselves up with some nice pitching improvements, as did the Twins, so they could be spoilers. I think the NL Central is more top-heavy with WS contending teams, but top to bottom, I think the AL Central might be a little tougher.
Back to the topic, it was surprising to see that the Yankees didn't make any drastic moves, but Girardi knows how to handle those guys, they need their young pitchers to step up, but can still be dangerous.