You just use one battery and switch for the ignition then two switches and batteries that will go into any open ports in the RX. Size of RX depends on how many channels you need. I use no Y-harnesses so I tend to need a bigger RX. You shouldn't need digital for a Cessna, just good analogs should be OK. Battery type?? I only have one charger for the newer types and several chargers for the older nimh and nicad so I only use the newer types in my electric planes. If I needed new chargers then I would go with the life and lipo packs.