I saw a motorcycle with a clear powder coat once. Looked amazing unless you got a few inches away from it. You could see every little imperfection where dust or something got on the frame prior to coating. If you're looking for a flawless powder coat, clear is not the way to go.

As for a winter project I'll be done with my new commuter by the middle of the week, so my next project is building up a 5 speed town bike. Using a 60s Western Flyer 3 speed frame because I've always liked their looks. I'm not sure whether I want 26, 27, or 700c rims yet. I guess it depends on what will fit. After this commuter I don't have the money for powder coating, so I'll be using automotive spray paint instead. I've had good luck with it on other applications, so I think a bike will be fine too.