I've only just begun to use what is officially documented, in your case it does sound like there could be some work reconnecting maps.
I know that the custom asset editor allows Enscape material definitions to be saved and loaded (right click on the names), but I am not sure if there is a way to export those definitions from a model for use in the custom asset editor. That is where you would cut out most of the extra steps if it is possible.
That time spent getting an asset to look great once in order to use it independently going forward doesn't seem like a waste of time if it is a piece that will be used often from scene to scene. I believe that is the entire purpose of the custom asset editor.