There is no such thing as "true redundancy". The closest you will come is to have a second airplane.
With that said, a bunch of extra failsafe stuff will not prevent someone from turning their radio on with the same frequency, or prevent midairs, or the engine from quiting in a hover, or the occasional dumbthumb. So going with a bunch of added "redundancy" equipment may end up as dead weight. Mind you, too, that with all the crashes that I have personally seen, giant scale or not, not a single one of them, in my 20 years of flying was the result of true electronic equipment failure. Sure, you will see planes go dead in the air and find the battery had taken a dump, but it was bad before the plane went into the air and the pilot didn't check the voltage under load right before the flight or he wold have caught it. And receivers have caused crashes, but only because the rx was not mounted properly or was in a previous crash, etc. Basically, most failures are pilot errors. Keep on top of stuff and you won't need all that redundancy weight.
The farthest I have gone is dual batteries with failsafe switches into a single rx. Beyond that, my redundancy comes from regular maintenance and inspection of my equipment. The result is a lighter plane and even less stuff to go wrong.