Change up the colorsMod: Fellout (Get it at )One of the design decisions that made the world of Fallout 3 so bleak was the color of the sky. That greenish tint gave everything a wasteland-like appearance, but the blue skies we've seen in the Fallout 4 trailers look much more inviting.
Thankfully, modders agree, and you can easily get that effect in Fallout 3 by installing Fellout. It removes the greenish tint from both indoor and outdoor settings, and makes days brighter and nights darker. There's also a that adds illuminated signs and street lights across the map to lighten up those darker nights.
Dn-3 Darker Nights (Level 3 - Medium). Dn-0-Ts-Fh Darker Nights for True Storms with Far Harbor (Level 0 - Darkest).