Julie, you are very right. Getting your blog set up to be as visible as possible to search engines, right off the bat, is time very well spent. :-) And I love doing blog marketing. You have a good intro list there. Social marketing is the third leg on this stool. :-)
But nothing ever beats great, on topic content! I guess we can call that the 'seat' on the three-legged stool, in this analogy.
A great blog can pull in residual income without needing much new activity if the "stool" is in place. :-)
Julie, are you willing to share your blog links for us to see what you've done?