I agree that a dynamic D/N cycle would be far better...
but on ther other hand I think I would prefer a cheap solution rather than nothing at all... If I had to choose.
I'm open to being corrected by someone more knowledgeable on the subject, but I don't think a basic day/night cycle in a simple version would be ludicrously expensive. Especially with Larian's budget. The most problematic thing I could see would be NPC schedules, but afaik these aren't very robust right know (if any schedules exist?).
So you could just do a simpler version of BG2:
- day with NPCs placed as they are now
- evening comes -> simple animation of sunset or whatever
- map transformed to the night version with appropriate cosmetics and some NPCs changed up (a vendor disappears - "went to sleep", creepy night creatures appear in the woods)
- morning comes -> sunrise animation
- rinse and repeat
Sure it would be
some work, maybe not an insignificant amount, but I don't think the cost of this would be prohibitive. Imo it's more a matter of Larian willing to do this or not.
(Of course, something more advanced would be very welcome...)