One of the things that probably keeps me away from here is level design, since I'm trying to build a career off it. I mostly design for games that are Quake-based in the engine field. Anything that can tolerate BSP geometry I can work with. I cannot 3D model which is something I'm trying to circumvent. One of these engine is Source.
Out of the 800+ level files I have, only about 10% have actually been completed, or got somewhere.
Some examples of incomplete but designs that got far. Note most of these structures are created by hand, but the editor does not have lighting previews:
This one didn't get very far but looks pretty nice. It was supposed to be Pripyat:
A joke map I was told to keep working on. I really don't know where to go with it:
Something for a mod I was making. I don't have an editor pic but here's one in-game: