On that image, you're seeing CSSET reintroducing the faking shadowing that was present in LE. It looks horrible in SE's lighting.
This mod is providing a few thousand unconflicted textures...so we're trying to judge based off a small set. Personally, I don't see any benefit of including this, however, on the flip side 90% of the "issues" are already overwritten by other mods in STEP...it's an odd and tough call.
I have to agree that it is a tough call for many reasons. I was trying to get my head around which textures will be used from this mod (that aren't overridden by other mods), but unfortunately Mod Organizer doesn't reveal the conflicts in BSAs yet and I'm not quite prepared to extract all BSAs to get a handle on it.