This looks good! There are some areas I'm not privvy to, mainly the fact that nights are now pitch black (realistically a night will only be pitch black if you are in a spot where there is heavy sky blocking like a forest, or the sky is ALSO black). Skyrim has too much ambient light, but ambient light in-general does have a purpose from an artistic standpoint - it is the light that the sky itself casts when it refracts and reflects the sun rays, which tints the atmosphere to be slightly blue, which in of itself acts as a very dull indirect lightsource.
In other words, shadows will never be very dark/black during daytime unless the area you are in has almost cave-like overgrowth, and night time will never be pitch black unless the sky is near equally black (no moons, no auroras, lots of cloud cover, etc), sans things like stars, which don't actually provide much ambient light.
Of course it can't be perfect. Skyrim for example has zero offical support for Ambient Occlusion (SSAO is one method of emulating this). Ambient occlusion is basically shadows created when the sky is blocked out, such as spaces under carriages or in areas where ambient lighting doesn't reach as much. It's pretty much the key to getting a well-lit scene that has good use of Ambient Light but also has a level of realistic depth and contrast to it to balance the ambient light.
I don't want to say this looks bad or anything, because it doesn't (and looks much better). I also love what you've done with areas like in that dwarven ruin. Personally though, I've got a nice shader setup that has things looking just the way I want. Atmospherics (i.e. distant mountains) have a blueish tint to them to match the atmospherics of the sky, which has a nice side effect of making my nights a little bit darker and appear much cooler in color, but still have a reasonable level of ambient light for my tastes

(example: http://i.imgur.com/5m42K.jpg )
Though honestly looking back at it, I wouldn't mind if it was a little darker. I'll probably try your mod out with my shader setup even though it might be way overload
