Well, because of the engines light restriction adding more lights might not work well, since you get artifacts if there are to many lightsources (objects flashing dark/light), i checked this, because i also noticed that the lights were placed only in some places while other areas missed it. I can cheat by adding gloweffects, this does not add lights, but can "simulate" emittance from torches and lights. The possibility that we can add more lights to the house with artifacts is slim, reposition lights and give them a bigger radius to cover more areas, is possible, but that might also make the house way to bright.
I can simply test this myself when i get the time, im not done with this mod yet.
I don't mean every object, things like randomly furnished candles would be nice but yeah that could be overload easily. What I do mean however is objects specifically crafted to emit light, such as the goat horn candle holders, chandeliers, and so forth. These objects often already appear to add additional light sources, but in a number of cases these light sources don't match the source they're supposed to come from. Off the top of my head, the goat horn candles in the back of the entrance way (towards the main hall) don't appear to properly have their light emitters on where the candles are, and the armory had all sorts of trouble with improperly placed lighting.
Is it possible to move the existing light added from crafting them onto the objects the light is supposed to be emitting from? It might require a few additional lights where they just stuck the light source in between candle holders, but it'd still be relying partially on just adjusting existing light sources.