Glad to hear you're inspired Russ!! I had another idea for my train room, which I didn't end up doing but I think it would work really well for your basement. Basically you build a room within the room - 2x4 studs, drywall and attach to floor and ceiling. In your case I would also lay some heavy plastic under the walls to protect from water damage.
The layout when complete will take up the whole room, so I am moving my workbench into another part of the basement. But before I can do that there is about 30 years worth of junk to get rid of!! There will be lots of room for storage under the layout too.
If you look at the trackplan I posted on page 1 of this thread you'll see that at the bottom right there is more space - a L-shape basically with another 10x25 area - currently filled with the above-mentioned junk, plus Christmas decorations, paint, tools, tool table, furnace, water heater, canvas stretchers and about a million books. I just need to clear a little space where it says "hidden staging" on the plan for my work desk, but I'll worry about that later.
Val