Luvtrains,
one of the things that might really help you is to use 5 different wire colors.
example
Outer loop center rail Blue
inner loop center rail Orange
accessory power yellow
Yard/switch power red
Or some variation depending on a number of things.
ground white
You should use no less than 8 barrier strips on that layout(maybe more).
in your case the wiring off the barrier strips would go to the TIU and other components would differ but the basic idea is there.
hope this helps.
