Have you considered working with 3D programs like Sketchup for your basic backgrounds?
This is actually a very good idea in terms of speed and ease, doing backgrounds with a program like Blender, Sketchup, 3DS Max, Maya, etc. Would really help when trying to make pages, especially if you're trying to get them to look proportionally correct and get them done in a timely manner. My comic uses 3D modeling in Blender for both characters and backgrounds (Although the characters have to be tweaked due to my style), which allows me to correct proportions, distance, and create awesome suits of armor that are the basis of the story 