It sounds overwhelming. I guess I'm not ever going to sell many books. Several of the things mentioned above - I don't even know what they mean. I have a blog page that tells people about my books, and they can find it if they go looking. But if I set out to become an expert in blogging as well as everything else, when would I write? Currently selling one or two a week, some excellent reviews, and maybe those readers will tell people who tell people.
But no. I'm doing my best to be a writer. There are only so many hours in a day, and so many days in a life-time. I don't want to waste my remaining days doing things I'm not interested in. That does mean, of course, that the unique experience of my particular book will be missed by millions. I guess, so be it. (Any smilies here? I want a resigned smile.)