Congratulations for your great work!

You say no private data is sent to the server. How can it be? I mean, the client must at least ask the server how much money it has on its addresses, what means the server will know which are your addresses, thus it will know how much money you've got on your wallet and how you spend them. Your "private data" is entirely known by the server.

Or by "private data" you meant only the private keys to the addresses? If that's the case, maybe you should correct your statement to make it clearer?

Thanks.