as far as the storage drivers go I have done the PoC for indexed db and it is very easy to swap to indexeddb if they wish. We can do this on the sdk side using localforage. As far as the encryption goes I am happy to then supply the wrapper as a separate package devs can use if they wish.

I have swapped it to the crypto web api which seems to work ok. I think we could have a quick chat to decide the best path.