It would add extra depth, especially for raiding, defending (traps) etc if the interior of buildings were dark all times of the day. Light would only be available through windows, open areas in a roof/doors or placed lighting. If none of those are present, then a personal light source would be needed.
Yes I was worried about the possibility of that. I am not sure how lighting is generated in the game. Day light seems to permeate everywhere, even caves. It would be nice if it was adjustable.
I really do wish we had the option to turn light bleeding on and off. 