We have reached a stage where people expect next gen graphics, and not even providing a current gen experience would be a great mistake. We are on the verge of a major improvement in graphics fidelity over the next 5 years and it's not because hardware is improving exponentially, it's because of new software techniques and previously unexplored hardware like "super fast" SSD's. Bannerlord is supposed to stay up and running for, I would say, at least 10 good years. If any developer is reading this I would advise TW team to set or revise the roadmap to improve the game engine over the next years.
That said, I would argue all times of day should get a revision to improve the graphical quality, realism and artistic direction.
GI (global illumination) and light in general are the certainly the big factors here. Many other ways of improving the visuals can and should be used. The particles engine, for example, which is currently underused given it's potential (side note - snow effects looks really fake). Just check out games like ghost of tsushima and many upcoming games like crimson desert, it gives a next gen feeling that's for sure.
The in-game lightening should be compared and carefully matched over a real reference in order to produce realistic scenes and characters. Study of light angles over different times of day and seasons, color and light spectrum, shadow length and intensity, all should match realism and the artistic direction. I'm no expert, the only thing I can do is try to create some awareness for devs in charge of this aspects.
As for night realism and artistic references, I will suggest the following.
Dusk time (example in the video above of Crimson desert trailer - 0:20; 2:29; 4:03)
Under Moonlight (in the Chrono odyssey trailer at 0:42 - troops in formation)
This is what I mean by the "artistic direction". This examples (above and below) show the silhouette effect which looks amazing both for combat and non-combat situations.