I don't know how to list your questions and answers effectively but will stumble through.
First, micros switch is no problem, BUT you wan feedback on and alarm FOB to show Open or Closed Condition?
Your second statement, disarming alarm with bolt retracted is a weakness, and you Trade Security for Convience. My Opinion
I am a Security System Contractor and like 12 Volts for My system and its devices, can easily be backed up with a Car Battery if needed during Extended Power Outages, I live in South Florida(Hurricanes) and it's nice to have Extended Time. So your thinking 9v or AAA's, ?.
SW. Some things don't need to be complicated, just have tampers, no matter whatever HighTech Protocol, end result is it needs voltage to retract.
The FOB and receiver is something I feel is seperate and should be considerd for it security in transmission, grabbing.