Come see this proof of concept I made. I linked async and threading through tokens, I also optimized all tasks, set up task failure retries, made a control interface on a WebSocket. WebSocket lets you decide what tasks are even allowed to exist in the mailing system (works but still in testing), threaded functions work in one line, it runs on the async event bus, synchronous functions can compute up to the number of async executers.... Yea, tokens are wild.

To describe it better: I made threads work concurrently with 0 task to completion waits and numerous parallel async executers acting on every function threaded by the token snapshot decorator to create tokens.