If you really don't like certain parts of what you do in Blender, you could always mostly do it in blender and then work on it in PS/GIMP/your choice of 2D graphic software?

If I can't get where I want to be with my CC3 map (and I will probably get 99% of it done in CC3) I'll probably add all the weathering of the rooftops (lichen and chimney stains and such) in GIMP