The above would be better suited to use cryptography technology.
What do you mean with '
cryptography technology' ?
Cryptography is a mandatory component of the blockchain.
There is little advantage to using blockchain technology for any of the above, because once an entity has access to the information, they can trivially replicate it in unencrypted format.
While you are right with some use cases, especially the patient chart, i disagree with all of these being unsuitable.
Digital Identity, would for example be used to 'sign' documents or contracts using a private key.
You could also implement something a viewing key to read the information (like with monero). So it wouldn't be publicly available for everyone and you'd have a proper handy system.