Haha! That's so true. Yeah, depth of the post is definitely something that's quite important. I'm still working on it today to be honest! My go to method for checking whether my post might be missing something actually comes from one of my clients. Ask yourself if any terms or concepts in the post lack explanation. If so, devote some time in the post to explaining them.
It's a lot harder than it seems, especially if you're writing on a subject that you're knowledgeable on. Some things may be common sense to you, but totally foreign to the reader!