I finally posted a new version of the real analysis book with the new metric space chapter, it weighs in at 192 pages now (with 12pt font though). It also fixes a now record number of errata; though my standard for what is an erratum rather than just a simple obvious typo has dropped slightly. One thing that makes me feel better about errata is that it seems Rudin’s 3rd edition of principles still has some errata that is essentially the same as what I did (independently, not that I really worry about taking credit for errata:).
The differential equations book nowadays seems to be hitting fewer and fewer problems: 6 errata in the past year, 2 of which have been in new stuff added before the summer. This is despite several people using the books and one ongoing partial translation. So I guess they are rather “correct” by now.
My goal right now is to get them to be correct rather than perfect. So I haven’t really been reordering things or rewriting things that could be improved. I’ve been at most doing small improvements in exposition. The main thing is that I want to spend time doing other things too of course:)