Let the debate begin on why the Tigers did not beat the Red Sox to make it to the World Series. As is typically the case, there really isn't one reason why the team did not win, but in the end I think it was about the Red Sox taking advantage of the Tiger's weaknesses.
Think back to spring training and what was the main question mark then? The bullpen. Without a doubt the bullpen was a glaring weakness that the Red Sox exploited, just about all of their runs came on two swings of the bat against bullpen pitchers. Problem is, if it were easy to fix a bullpen, it would have been done, good closers aren't readily available unless you do what the Red Sox did and head to Japan.
My main quibble with Jim Leyland is that he kept managing as if he had a good bullpen, when he clearly did not. I think that when you are in a championship series you ride your starting pitching until they lose. The bullpen is made up of professionals, but none who would be sought out to be on the bullpen of any other team in the MLB.
Beyond the bullpen, and finding a replacement for Jim Leyland, the biggest issue the Tigers face is what do with Cabrera, Fielder, and Martinez. In hindsight, panic over Martinez's knee injury two seasons ago lead to this problem: Cabrera's bat is too important for him to be playing third base. Fielder can't play anything but first or DH, and Leyland didn't want to put Martinez behind the plate.
Unless Martinez catches more next year, I think he or Fielder ought to be traded, preferably for some bullpen help. Bottom line, what the Tigers ought to have learned is that Miggy must be moved back to first next season.Playing Miggy at third base is too great a risk to his health, and we saw first hand since September the affect of Miggy not able to be a threat in the line up.