Neat idea. Odd that those diagonal telescoping rods don't interfere with the yagi pattern?

Put the volt-meter in series with a switch or momentary button. They tend to draw a little power, so you don't want it draining your battery when you are not using it. If you stick a cig (accessory) port in there too, you could plug in other things, or a usb charger or whatever if needed. I've used my pota battery to run a small 12v air compressor, for instance.

Amateur radios are generally spec'd at 13.8v plus or minus either 10% or 15% so that they work on a non-running car (12.something volts) or if an alternator is running a bit hot. A 100W radio like this is pretty much always going to require around 20amps at full power -but they have adjustable transmit power. They don't transmit as well at the lower voltage range, but most people don't worry about it.

It's a (kind of silly) throwback to the radios that armies used in the first half of the 20th century that were large enough to necessitate a dedicated person backpacking them around everywhere. It's still common in ham radio like other traditionalist terms. "Portable station" is more accurate, but maybe boring?

I would look at fabbing up a box that fits snugly, rather than "clamping" them. That could protect against puncture as well. A 3d print or thin plywood glued together would be fine.

This is a really good take. I have enjoyed the serialized shows -but they are a juggernaut of emotion and intensity to watch. You tend to watch them once, and it's a fairly wild ride, but then it's done. I suspect that I will be re-watching episodes of SNW and lower decks for years to come, as I have for TOS and TNG. That's how Trek wormed it's way into my brain in the first place.