As a user, internal or not, I strongly wish that your app WOULD lose its identity. I don't want your app to have a separate identity; I want it to look and feel exactly like everything else I already know how to use, so I don't have to waste any additional time getting familiar with it. I don't want "something interesting", I want "a tool to get my job done", and the more you try to push a brand and make your app distinctive, the harder it is for me to plow past all that and get to what I really want to do.