I don't cook in the oven anymore.  

But in the "olden times" roasts followed by baked custards or cakes helped to moisten the walls of the oven and easier to clean at washing up time.  (Bit like boiling a cup of water in the microwave for 30 seconds.)

Uneven cooking within the oven can be due to the oven not being level.

Hope this helps.

DEB