Mmmmh, lookdev is typically done in many scenarios e.g. from studio neutral, to overcast and daylight. There is simply no way for an asset whose appearance was developed under flat lighting conditions to look great in daylight. Assets must be tested under the most varied lighting conditions possible or at least those representative of that they will be subjected to in the show. The corollary is ensuring that the asset looks great at all the exposure levels.
This is probably a question for Epic Games
Probably for Epic Games too!
I wish I could answer your remaining questions but I contractually cannot!
If you have UDN access, I would probably also consider asking that over there!