You should realize that even major startups blogs will only get you a relatively small amount of traffic (less than say being on the front page of HN) and most of that traffic won't be sticky, the value of being on the front page of say Techcrunch is that it puts you infront of potential investors and partners.

And you lose a lot of that value when you go to second or third tier startup blogs. You're much better off going for blogs which are in the same field as your startup (i.e. a health startup should go for health blogs) as you're much more likely to find actual users there.