How does Account Abstraction improve the UX compared to other methods?

Account abstraction means only smart contracts can hold assets. And so every wallet interaction is done through a smart contract call, to smart contract code. Ideas where this could mean better UX:

1. Native meta transactions. Have your users sign their account's calls, then broadcast the payload and pay for fees for them
2. Fee payment in any token you like by using gas stations
3. Session keys, where you delegate signing power for a short while to an operator to avoid signing thousands of txs
4. Social recovery mechanism in case of loss of keys
5. Upgradable account contract code to benefit from new features when they are released, without migrating funds in masse