Thanks for your time & sharing your lighting settings…
Before I try them; I have 2 questions through what I see in your posted images…
- In the outdoor images there were some clouds in the (background) sky… does this has any relation with the **skylight **you used…!!? OR it was a mesh (textured sphere)…?
- Did you use the same settings for the indoor production images?
The new Grass pushed your production for more awesome reality 
BTW; I found a cool thread talking about creating grass… in case you hadn’t see it before
https://forums.unrealengine.com/showthread.php?3268-Nature-Environment-in-UE4&highlight=ulrich
keep on
My best wishes