My favorite theologian wrote a good book on the philosopher I hope to better understand:
Thomas C. Oden, “The Parables of Kirkegaard.”
Others that I have recently read include the first couple of books in a Dean Koontz series “The Silent Corner” (Jane Hawk Series.)
I just started Tom Holland’s “Pax” about the time of Rome after the four emperors period — I read all the Tom Holland I can find.
The third book in a Dave Weber / Chris Kennedy saga, “To Challenge Heaven”.
D’Ambrosio wrote a good book, “When The Church was Young, Voices of the Early Fathers.” This is a “don’t miss.”
I have started, Wilson’s “The Thirty Years War”
I have muddled through “ Horus Rising. book One of the Horus Heresy although I doubt I will do the next fifty in that series.
I have in the “on deck circle” Brunt’s “The Mysterious Case of Rudolph Diesel, Genius, Power and Deception on the Eve of World War I”
Likewise the first two books in The Tyrant Philosophers series by Adrian Tchaikovsky who is probably one of the best new SF writers out there.
Di Spigna has out “Founding Martyr, The Life and Death of Dr. Joseph Warren” and I have about a hundred pages read.
I have started Dixon’s “Who the Hell if Frederick Nietzsche”
I finished all the Martha Wells, “Murderbot” series which is pretty good if SF is a thing you like.
Likewise for SF bubble gum for the eyes reading I have done about 30 in the Michael Anderle, Kurtherian universe series — senseless drivel but I liked some of it.
There is couple of dozen more I could list but that’s a good start. When you’re retired you have a lot of time between yard work and house maintenance.