Can I give you a bit of constructive criticism, writer to writer – actually, non-writer to writer? I understand your strategy, but I think there might be better ways of doing it. Including your novel title and link in your comments on unrelated articles is borderline spamming. I’m not familiar with the rules on Medium, but on many other platforms that might even get you banned.
I think a better long-term strategy would be to engage in a conversation with other users, write about your experience, gain some followers. You might even post excerpts of your novel or publish a few posts about your writing process. And you can have your book title and links on your bio, so that people see them when they click your profile. That’s the way most published authors leverage their audience on Medium. It seems to be working well for them.