I like this idea, the cost should also not be an incredibly high amount to recover your account. You say

For example to prevent abuse it might be necessary to limit account recovery insurance to being a one time deal where you get one time per individual to rely on it."

I would maybe suggest a time line rather such as once a year, as these things can happen more than once. Or a loyalty system, you start at a 100 and when you recover it it takes you down to 0, and you then need to work your way back up by being active, posting, curating (the usual) before you would be able to do it again to stop abuse.

:)