I read the same books you did, and I was equally unsatisfied afterwards. The "Using Asyncio in Python 3" book was good enough to help me write some code that had to hit an API 400k times without blocking, but I never returned to asyncio after that.

Afterwards, I realized there was a package called aiohttp that I could've used, but too late.

I'll be interested to see what other HN people have done.