As a free software maintainer, I have high standards for quality because (a) I like it that way, and liking it is why I do it for free, and (b) if your PR sucks

As a free software maintainer, I have high standards for quality because (a) I like it that way, and liking it is why I do it for free, and (b) if your PR sucks, chances are I'm the one who has to write the docs, fix the bugs, and deal with the design consequences forever. If you disagree with maintainer priorities, just fork it! Merge whatever you want, advertise your fork in the unmerged PRs' comments, see what happens. Nobody will be offended; the license specifically encourages this. Maybe you'll find you're just better at this maintainer thing and the world now contains better software, or maybe after a few years you'll find that you understand their perspective.