Talk about battery basics - safety with charging (i.e., NEVER leave your batteries unattended while charging, when not to continue using a battery, 2s vs. 3s vs. 4s, perhaps. I know it seems REALLY basic stuff, but I see a lot of different questions on batteries and how to care for them. Might be good for an episode.
Something else to cover would be transmitter basics - not so much brand specifics, but things like different protocols, how many channels you may want, why cheaper isn't always better (i.e., a cheaper used DX6i is limited to 10 models but the more expensive DX6 has up to 250 models it can store), ergonomics of the radio (if it doesn't feel comfortable in your hands at the start, is it going to feel comfortable while flying for 10 minutes or more?), support for setting up the radio - i.e., if you're flying at a club and everyone's flying Spektrum, or Futaba, or Graupner, but you bought a FrSky radio, odds are good nobody there is going to know how to configure your radio. Or, you've got a problem with the radio that falls under warranty - does the manufacturer take care of you, or are you going to have to jump through hoops? And is the manual easily readable, or was it written in programming language and translated to Chinese, and then from Chinese to English, where there might be mistakes that don't make sense?
Those are some big things to tackle, I know.
