The only thing promotion does is skew search results in favor of your blog, at the expense of other blogs which address the same problem. If your writing really is better, this is completely unnecessary.
It seems like you crave attention more than anything, which is certainly a nobler goal than blogging strictly for money, but in the long run, you're only going to attract readers who also crave attention. Once you're no longer capable of giving them that attention, they will go somewhere else.
There is a "wall" between blogs like yours and the ones that really take off, and it's entirely based on the author's motivations.
On the other hand, the only promotion from the post that helps searchs results is commenting in other blogs, and not in all (because of the "nofollow" tag). All the steps I suggest has 0 net effect with search results. To rank high you either need to be linked to, be the only one addressing the problem, or do some kind of black google magic.
Finally, being both Hacker News readers, I am really interested in knowing which are these blogs (as we both read here, if they interest you they probably may interest me), and I want to see what they are about.
I wrote this as a guest post from my own experience for sharing my posts, where I write (except maybe in some case, I can be sure after more than 700 posts) only original content. But before I started actively promoting my content, I had mostly readers coming from Google to a few selected places (very few). After good promotion, my posts started finding readers, and when they were interested, they delved deeper in my blog, finding my old posts. My subscribers grew (I've tripled since I started my blog seriously), and so did my interactions.
But as you say, there are zillions of repetitions among the blogosphere (I've seen it also, all over the place) and this is completely sick. But as it stands, it is and endless run: if I create good original content without promotion, the repetition people will just fill the place and no-one will read what I have to say. And I enjoy too much blogging (blogging with readers... if I want to write for myself, I'll do journaling) to be forced to give up.