Better pitching, better hitting and, more importantly, better attitudes.
The new GM in KC was being groomed to take over Sherholtz's (spell?) spot in Atlanta, before he was hired by KC....and is highly regarded in the league. He made a number of "under the radar" moves before the trade deadline as soon as he got there last summer (ie., getting rid of either poor attitudes or work ethic) and during the winter, including purging of Affeldt and Sisco. I also believe they also have 3 or 4 of the top 20 minor league prospects.
It will take some time and there are limits for the small market club, but they are headed in the right direction. There is also less interference from the owners.