Mark, I thought I'd pass along something that I learned during the track-laying phase of my layout, which shares many similarities. You mentioned fitting the track tightly in the corners. If you plan to run any long locomotives or rolling stock (such as heavyweight passenger cars), make sure to allow for overhang. You'd be surprised at how far beyond the outside rail a loco's "cowcatcher" or the corner of a long passenger car extends when negotiating a curve, even those with a big radius. My outer curves are 096 (Fastrack), which has the built-in "road bed" that extends beyond the crossties, yet I still have to allow extra space to prevent my PRR heavyweights from bumping the wall at the curve exits. The only way to be certain is to run the biggest thing you plan to use on your layout and physically check the clearance. Don't forget to account for any scenery that might occupy your walls.
Keep up the great work!
