Darren,
One thing I'm concerned about with the horseshoe design is fitting the loops inside each other on both ends of tracks 1&2. (Track 2 is the over/under inside loop). Right now I'm using a 5.5" piece to expand the Track 1 outer loop, but I'm not sure that's going to be enough.
I'm also considering lowering the Track 2 inner loop 3" so that Track 3 doesn't have to be so high. By lowering the whole loop, the grade will start at -3" and rise going around the loops to +3" back in the center of the dogbone.
I'm still concerned about being able to reach the tracks along the wall on the right. Mind you, with O54 curves back there, I don't expect to have many problems, but it's still something to think about. Again, the whole back of that shelf where Bedford Falls will be is going to be removable in sections that can be handled easily. I intend to run a track cleaning car, but I'm still concerned about cleaning track more than derailments. etc.
I actually want to make Level 3 completely removable in 4 sections. That's why I'm still considering 1/2" plywood for the sub-roadbed with sound-deadening board for the roadbed, at least for Level 3.
