If it's a paragraph, it's a post. Medium-sized content gets short shrift these days. Don't go long. One or two paragraphs count. Then press publish.
I disagree with this just a little: "If it's a paragraph, it can be a post."
Negotiate a comfort zone on two axes: personal and public, tech and everything else (feminism, musical theater, MMA, parenting, etc). 2001-era Scribbling.net was too personal, Lifehacker/Smarterware too tech. There's something in the middle.
Yep. Totally agree.
Traffic is irrelevant. Don't even measure it.
Simplify, simplify. No comments. (Maybe G+ or Disqus later on?) Use Markdown and Draft to write. No pages, no requiring an image every post. No categories, tags, footnotes, special post styles, pages. Virtually no plugins. Default WordPress installation with the most stripped-down theme possible.
Somewhat agreed, somewhat disagreed. No comments, that is ok - but receiving pingbacks and webmentions1 in my opinion are important; that is how you keep the web alive.
Categories and tags are only useful if you actually use them for anything, so if you don't, forget about them; that I agree with.
Virtually no plugins: yes. Also, find a lightweight - as in computing requirements - theme. It'll do miracle to a WordPress site.
Ask for trusted collaborator feedback. Clarify ideas when you're not sure how they come across. Run a draft by people you trust.
For example, a spouse for proofreading is always helpful :)
Have fun. Blogging is not your job. Don't add it to your to-do list. If it's not fun and you're not done? Screw it. Take the baby to the park instead.