I've been exploring Prismacolor pencils lately.
Any modeler, I think AutoCAD is nice to start with then finish up in
3ds, but that's a lot of green and a lot of learning. Right now I'm
very keen on the Maxwell renderer; the closest to single button first
pass rendering solution I've seen, by far. Available standalone and
with plugins for many modelers.
Some interesting work has been done with Piranesi, but not by me.