i have a network of more then 300 blogs
though blogs are hosted at blobspot but i put salt in Google eyes creating more accounts and use 1 email for every 3 blogs so Google consider them unique from different unique accounts/webmasters
i am on the random IP so no worries about login to accounts from same IP

in marketing it gives me plus point to link each other so i put links in Blogroll for each other

the other plus point is i place sharing buttons to social media sites and get some good shares

as i don't believe in BUY Traffic can you suggest me some more ways to market a set of more then 300 blogs altogether