Hi Tom, the attached Lionel manual may help you with the wiring. You have a fantastic layout!
On Page 40 is how you can wire a UCS track with separate power. I have done this on a siding that usually has the power turned off by the use of a fiber pin in the center rail. Not sure how you are using your transformers. it is possible to "phase" transformers together in order to use more than one on a layout. Page 45 has a section on "how to connect transformers in parallel".
All the best and good luck!