"Generator Mode" theft prevention methods.

I know that every few years, some sort of "Prius as an emergency backup generator" thread gets traction. I have a good handle on the various versions of that, but one thing that I don't think has ever been fully solved, is the security problem it can create, depending upon your location/situation.

This thread is an attempt to resolve that.

As an aside, my own motivation to solve it, and to put in some real work on it, is not primarily for when using my Prime as a house-backup generator. It is actually for a couple of very different scenarios, with the exact same security problems, and presumably the same solutions. I'd be happy to start threads on the two other scenarios I'll use the solution for, after solving this. But for now let's just view this thread as an attempt to definitively solve the general problem:

"Theft Prevention for a Prius Prime Left in Ready Mode"

The situations where I've badly needed the above solution, have usually (but far from always) been in places where I was semi-comfortable with the easiest solution:

SOLUTION #1: Close up the car, lock it using the physical key in the driver's door, and take the key and all fobs with you when you leave the car unattended.
Pros: It disables the key fobs and disables touch unlocking.
You need to use the physical key to open it.
Very easy.
You have the option to make it look like you may be (living and/or sleeping) in the car.
In some situations, that will discourage a breakin.
In some situations, that will encourage a breakin.
Cons: Someone can break in and drive the car away.
They could drive it anywhere, not that a typical car thief takes it far.

SOLUTION #2: Solution #1, plus a Denver Boot type device on a wheel.
Pros: It disables the key fob and disables touch unlocking.
You need to use the physical key to open car.
Still easy enough.
Cons: Need an industrial-strength boot, otherwise same cons as #1, just delays them.
For situations different than generator, keeps you from leaving quickly.

SOLUTION #3: Lock shifter from working.
Many different designs possible, with different pros/cons.
Likely Pro: Car remains Ready, house remains powered by car, car can't drive.
Simplest idea, let the car be Ready, but unable to get power to the wheels.
Some ways are physical, some are kill-switch-like, some are key-switch-like.
I think the better ways of doing it are easy to make work, hard to make truly secure.
The easier ways might stop 80% of car thieves.
Maybe a combo of easy ways would stop 95%.
Hard ways might stop anyone but a Toyota tech.

SOLUTION #4: Kill switch on high voltage line to MG2.
Pros: Pretty badass solution if it works!
Cons: Can't kill-switch MG1 also, because MG1 charges traction battery.
I think car can operate as HV without MG2, with MG1 being what ICE pushes against?

SOLUTION #5: Have thief's presence turn off ignition, making car no longer Ready.
Pros: Could be pretty simple alarm/relay, and if it works, extremely secure once tripped.
Unlike seeing a key/kill switch to try to defeat in #3, he has every reason to leave.
Alarm could also trigger horn/siren/etc.
Cons: Basically none, it puts thief in same position he'd be in after breaking into a random car that's off.
I guess you'd end up with a drained 12V battery if your inverter to house runs with ignition off.
So it would be wise to have a relay to only power your house when ignition is on.

SOLUTIONS #6-#100 Things you think up.

SOLUTION #101 Some foolproof combination of the above that evolves from this.