I did some more research and I think I actually end up with something slick while keeping some semblance of safety
It kind of looks like what you described, but instead of the kill switch being physical, it'd be electronic
There are tons of RFID sets that essentially turn a relay on when you get close enough (and making my own with some smarts to prevent accidentally running down the battery would be pretty straight forward)
I did some more research and I can wire the immobilizer coil to check for the RFID pill without putting my key into the cylinder
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So what I would do is wire the immobilizer coil to turn on when the tag is in range, then wire a "push to start" switch as normal.
That way the RFID setup becomes the "immobilizer" and as an added bonus, I can make as many "keys" as I want
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Of course, someone clever could always tear open the dash and hot wire it at this point, but I feel like if someone is able to tear open my dash, get at the ignition switch, wire it all together, they're also probably smart enough to figure out the immobilizer bypass that exists for the stock immobilizer (if anything, they might case the car expecting that to work and be in for an unpleasant surprise
)
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My main concern is the extra keys. I could stop being a tightwad and just spring for extra keys with Option 2 since you confirmed that does do what option 1 would, but the tinkerer in me would love to work on this
and get to cut the dealer out of the process of getting new keys