I'm just going to randomly start dumping some sketches here that I've done for various maps. To start, here's the sketches I made for my 7.2 hour map, ad_relay:
The sketches are out of order, I designed point 2 first, followed by 3 then 1. The final product is a bit different, (most notably I cut a bunch of the angular geometry between points 1 and 2 to keep my sanity during the stream) but you can still tell that it's the same map. I'll see if I can dig up my drawings for my various other maps later, as well as the initial sketches for what became Reactor (those might be a bit harder, some of them were in my AP Calculus notes (which I don't have with me)).