The whitespace and font size you have now is good. On HN, I have to zoom in to 140% to be able to read comfortably. Just went back to 100% and quickly remembered why I had it zoomed in.

No one is using 480p CRTs anymore, IDK why HN is still formatted that way. Regardless, I like how it is. My scroll wheel is not poisonous, I'm happy to use it.