Hi all, Yes track planning SW is a very nice invention. I get to change my mind as often as I like, prior to actually building. Four designs later this is what it will be…
the office is 16 x 11.5ft (give or take), the elevated track is mounted 12" below the suspended ceiling. It will be all Aristo track and should serve the purpose rather nicely. Minimum radius is 39" - center portion of the curves - the rest is 48". I’ll report on the performance of the turnouts 
The siding has 6ft capacity, long enough for what’s planned.