@dzham
Having 2FA as part of the login process is currently what I'm working on, so keys are not sent to the user if 2FA fails just as you described above. Regardless, the secret keys are encrypted with keys derived from PBKDF2 so the user still needs the password used in deriving the encryption key before they can sign transactions with the secret keys.
Agreed a multisig account will be more "secure" but I don't think it's the place of wallet to place such a restriction on the account. The owner of the account should be able to perform transactions outside the wallet if they so choose.
I think it might be best to advise the user on the benefits of a multisig account. They can have an account used just for signing and they keep that secret offline. When it is time to authorise a transaction, they can add the extra signer.
Maybe I can add that to the transaction forms; a place to enter extra keys required for signing.
thanks for the feedback... keep 'em coming ?