For your possible interest, my own https://chrismorgan.info/atom.xsl is the most thorough Atom Feed Document stylesheet that I know of.

(I did also make an RSS version of it, https://temp.chrismorgan.info/2022-05-10-rss.xsl, including handling RSS’s stupid date format as perfectly as possible for some reason. It would actually be a useful guide for reversing that process, too…)

For maximum enthusiasm in this direction, make posts actual Atom Entry Documents. Will it benefit anyone? … well, I suppose it could be convenient for tooling to make a feed by just concatenating documents.