If you like the classics, you'll probably enjoy my other newsletter as well - http://waybackletter.com.
I would also mention, one huge reason I use hacker news is for the comments. If the summary could just mention a couple major topics of discussion, e.g. the 'good stuff' it would make a summary useful to me there as well.
More broadly, I noticed that all your links are the articles, with companion comments. You do have a few 'ask HN' and similar thread posts, but perhaps consider highlighting those occasional remarkable discussion threads on their own, or quoting excellent posts. I've saved more than a few HN comments myself, and a couple great quotes at the end could be a nice 'wrap-up' and bring some of the community discussion feel to the format.
also points and number of comments are important things to be included in email, but they may clutter it. personally i prefer them to be there.
and the classics part is really good ;)