I have now reviewed this PEP (and the thread here - phew!) and I’m pleased to say that PEP 735 (Dependency Groups) is accepted 
Congratulations, @sirosen - this was a long, complex discussion and you handled it really well, keeping things on track without shutting down important debates. For a first PEP, it was a very impressive performance!
This is a very good point, and in my opinion was a key factor in the success of the PEP. It would have been very easy to try to support everything in one go, and end up with a complex specification with a bunch of incompletely understood edge cases. By deferring complex questions for future extensions, you’ve established a solid base for the feature without locking us out of further capabilities in future. That’s a useful lesson for authors of other PEPs to learn.