I guess if you want to just sort of vaguely gesture toward things that were very obviously the point and focus of the novels, and things that they do better than the vast majority of books, and instead lament the nominal failure to expand on side issues that aren’t even relevant to anything else, then you’re free to do so. I really don’t see the point though.
To me, it’s as if you’re looking at Van Gogh’s Starry Night and saying, “Well yeah, the colors and texture and movement and composition are all great and all, but I’m just disappointed that there aren’t any people in Victorian dress in it. And not even one madonna and child!”