We've come up with a final list of issues that will block the release of yt 3.4:
If you know of any issues that you think should be addressed before we release yt 3.4, please speak up.
If you are interested in working on any of these issues, please feel free. If someone has already assigned it to themselves you may want to check with them first. If no one has been assigned an issue you're interested in fixing, feel free to issue a pull request for it.
Hopefully we'll be able to get yt 3.4 out soon :)