Dual recievers- or two seperate batteries?
You did say this was H9's 1/4 scale CAP, right?
Sounds to me like your contemplating rigging a larger model, a much larger model.
For various reasons, weight being the primary one. You just don't need all this redundant equipment which leads to complexity, additional failure sources and expense.
The simple approach is often the best methodology.
I'd suggest that you have too much rudder servo. A jumbo is heavy, uses lots of power and is large. I'd use a high end standard size Digital servo for rudder. This is more than adequate on this model.
One RX, one HD switch harness, 4 or 5-cell battery with at least a 1400mAh rating, or more.