Certainly an electonic option to evaluate would be the Turnigy Receiver Controlled Switch. It can be used to switch a circuit with a secondary battery, or a load through the primary battery. In this way you would be able to power lights through the switch without drawing power from the Rx.
http://www.hobbycity.com/hobbycity/s...idProduct=8833
Should be an option. The MERS will also function in the same way I think, but the Turnigy is around 10 bucks.