To be decentralized, it seems like a minimum requirement should be something like this: you should have no single point of failure.

This is a good one!

Changing your private/public key is changing who you are no? Is like shooting yourself in the foot. This is more about ownership but maybe a better example would be multisig or that you break a key into pieces so that if it gets stolen then nothing is really lost, as others a guarding the rest of it. I'm not sure but Criag Wright talked about it in the latest Future of bitcoin presentation.

I get into this stuff - I think decentralization theory is really interesting, just like you. If you like thinking about this, I'd say it makes you curious. :)

Nice, I'll be posting in a few hours that what was uploaded just 10% last time, I'll be curious to know what you think :)