I'll take a different tack here and say why not use the de facto RPC language of the Internet? I.e. HTTP REST APIs?
With Python Requests on the client side and Flask on the server side, you get these kinds of benefits:
- Existing HTTP REST tools like Postman can access and test your server.
- Those same tools can document your API.
- If you also use JSON, then you get a lot of tooling that works with that too.
- You get proven security practices and solutions (session based security and SSL).
- It's a familiar pattern for a lot of different developers.