I have been working in blender for the past day making various modular environmental art pieces.
This all started when I saw a talk by two people from Bethesda Games Studios talk about their level design process of fallout 4 on the GDC youtube channel.
The talk is called Fallout 4's Modular Level Design and you should watch it. Lots of good stuff and examples on how they use prefabs and the like.
Anyway - I have been working on some modular environment pieces. Which I am super happy with so far however nothing is textured yet.
My end goal is to make a series of Modular kits for my game.