I was thinking about working on RBF.
To detect or create RBF transactions? For both you would need the C++ side to feed you some sort of RBF flag for each UTXOs. I created a branch on my fork called RBF_PR. It is based off of master. Feel free to fork that repo and work in that branch. Assume you are getting an RBF flag from ZC UTXOs, I'll add that extra bit of information once I'm done with the new DB. Please keep it all on the Python to simplify the merge.
Also, what about work on gitian/deterministic builds?
I can't use any of that, will have to go at it from scratch too. Not sure about the priority on this, although I value that feature a lot.