I have to say I agree … the current delivery does sometimes strike me as being a little too large but on the other hand the spacious clean UI itself benefits from it and I would not want to see the UI compromised. I think a user configured tweak option would be perhaps the best mid-ground (although I guess a lot more work for the devs)
I see that most of you here want to just control the size yourself. That looks like a great idea. But I am writing this to let you know that I don’t mind the size of current headings. I give lectures everyday looking at my Bear notes and I benefit greatly from the large headings. Afterall, headings are supposed to stand out so that you can find information quickly. I frequently glance at those headings during my presentation and the large headings help me greatly. I even choose a theme that makes headings contrast greatly from the body so that I can find information at a glance.
Why hasn’t this still been addressed? This drives me nuts. Its the only odd thing about bear from the otherwise extremely polished experience. The headings are too large. Otherwise give us the option to set it.