Hi Damian,
Sorry for the late reply.
There are two things why I didn't use Stem.
1. A number of python implementations I've found on the internet had broken dependencies or didn't work at all. So, I decided to create a fully functional Tor client with the bare minimum of dependencies.
2. Up until now I thought Stem was just a library to control the Tor process. As it said at front of https://stem.torproject.org: "With it you can use Tor's control protocol to script against the Tor process". Unfortunately API docs didn't help me to see that certain Tor primitives were indeed implemented.
If you'd care to integrate any of this functionality into Stem I'd be delighted to work with you.
I didn't yet think about integration. It's always a matter of spare time. Anyway, you can freely use the code or send me bugs. In turn, I can help you to resolve the issues.
Cheers.