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.
Eliminate the racist "Chiefs" nickname and become the Kansas City Ermines. It's time, people.