Extra weight for links to a homepage is unconfirmed. Links from real, editorially run sites beating fake blogs is confirmed in spirit, because SpamBrain targets sites that exist to pass links. Blog comments are content, not a ranking bonus, and their links belong under ugc. Guest posting reaches readers, but guest posts with optimized anchors are spam. The Google+ Circles claim is obsolete: consumer Google+ shut down on 2 April 2019. The durable strategy is to publish something others want to cite.