Dave,
You are correct on all counts! I realize I will need steep grades and level areas for the switches. The prototype is steep, and I'll be running short trains. I have never used curved switches before, even in HO. Straight ones would be less expensive as well. Yes, I have bent GarGraves before for a little jog in one wall on the Ceiling Central, and yes it is a bear! I am up for it where necessary however, and I realize the yard and turntable area will need it.
As to longer trains, I already started refitting one corner of my Ceiling Central RR with 072 to run them. I agree with John C that trying to fit an upper loop for them in the adjacent train room would be just too much!
Thank you for taking a look. I hope the train show in Phoenix was good! Enjoy the weather. It is 14 degrees here.