Okay, jr switch, here's my layout. It's a freelanced Canadian shortline, starting at an interchange yard (marked A) and going around counter-clockwise through the turn at B and goint to C, then back again. Along the way, it delivers cars from the interchange and picks up empties or deliveries to leave back at the interchange.
I'm thinking about putting in a small (90') turntable at C, so the engine can turn around for the return trip. If I do that, though, I need a way to turn around again somewhere near the beginning, and I don't see a way to do that. (I did toy with the idea of elevating the C end and having a wye near A that went under C, but I couldn't work it out without a pretty bad grade, which I want to keep under 2%.
The connection from B to A is to provide the ability for continuous running, but it would not be used in normal operations.
Let's see, what else?
There is a duckunder, but I couldn't really help it to maximize the space. The top and left side are against the walls.
There is one small aisle space that is only 18" wide, but that's only for maintenance access and not normal operation, so I think it's okay.
If you (or anyone) has suggestions, especially a way to turn the engine at C and A, I'd love to hear them!