Best practices to patch Linux servers

I know this is not a first time people asking this question, but yes never i found a satisfied solution that i can implement. See my requirement below.
Out of this discussion I wanted to know one (of course standard way) of the best ways to implement patching in my environment. Currently I follow patching automation using a standard shell script in combination with RHN API. My current systems setup as follows.

I manage 2000+ RHEL server (5,6 and 7)
All servers are connected to RHN satellite
Patching policy is quarterly.

Does anyone has better approach then what i follow, please help me out.