I like the change, but dragons beware. They support the hash format for decades, but almost nobody uses it. I almost wanted to implement the hash lookup by myself, until I found out, it's already in there. Ready for primetime, but I suspect many packages will run a afoul.
Same thinking here; how much speed up are we talking about as approach b, as suggested to have the preference, still involves maintenance due to upstream not taking this. What is the ROI?