Read clusters of five books. Visualize clusters as instruments to inspect the world. Collect instruments into a mental lab. Read ~40 pages/day. That's ~20 books/year, 40 new instruments per decade.
This post was so good that I upgraded to paid just to comment on it. Would you be open to sharing your sets of 5 books and the rationale for choosing them? I've (completely unintentionally) had similar periods of reading, so this really resonated.
I try to do something similar: either read one book on a topic, or read enough books on a topic that I can be inside the OODA loop, can skim bits that I've seen before, can identify cases where one writer is selectively reporting something ambiguous, or where a book omits something important.
I think some form of note-taking and spaced repetition on top of this - I use Roam - would be golden.