2.4 ghz is one solution.
They make optical isolators. There are may routes that RF can take back to your RX. Make sure your throttle pushrod is nyrod, and not metal from contact to contact. Put the RF filters on the throttle servo lead. The aluminum tape sounds like a good idea, and maybe people use it, but I might worry about what happens if you are flying the plane at an attitude straight toward you...Does it deflect your radio signal? Just a thought.
Right now I only have one gasser. It was flown on 72 Mhz with no problems for about a year, and then I switched over to 2.4 and (still) no problems. I will soon be flying two gassers, both on 2.4 ghz, so I'm not too concerned about interference...But I'm still not getting sloppy with it..