The way I see Berry so far is that he's great at run enforcement and is a sideline to sideline guy in that respect. In pass coverage, he's good at both man to man and at being a center fielder type of safety. However, his weakness is in figuring out who to cover and where to be in coverage.
I don't know what that means, other than that there are two good roles for him: a strong safety run stopper who lives in the box (what he does now), or a deep free safety who cleans up other's mistakes. I actually think his current role is the best fit right now.
In the final seven games of the 2013 season, the Chiefs averaged 34.6 points per game, scored 38 points or more 4 times, and went 2-5. The NFL has ruined the sport.