OK first get rid of Google plus and twitter because they are useless. Twitter is highly censored and seems to focus and promote too much celebrity bullshit and Google Plus and the worst website I have ever seen or heard of. Google plus is so bad that just its existence has worsened other sites (YouTube,) its so bad that people like me (YouTube users) were FORCED to use and accept it because Google knew the only way they could gather an audience for Google Plus was by sucking the blood out of YouTube (YouTube was not even their idea or creation.)
So now we are left with Steemit, Facebook and Reddit. Steemit is good in a lot of ways but I have noticed it seems to suffer from a small pool of readers. If I post a link on Reddit or Facebook it can bring thousands of people to my site. Steemit seems to lack the ability to do this it may bring 20 or 30 visitors but thats about it. It could get better as time goes on but right now the only thing good about Steemit is it pays cryptocurrency for your posts.
Now we are left with Facebook and Reddit. Facebook should be the most useful one of them all because it has the most users but heavy censorship has ruined it. It does still have its uses and is very hit and miss. If I post everyday or even every week my posts can still reach thousands of people. Facebook have also locked me out of two accounts and made its self as useless as possible.
Reddit seems to me to be the most effective way of sharing yours blogs! It is far from perfect though and still censored. Its overly strict on new accounts I only signed up a week ago and because of this I am flagged for spam when I post despite a capta solving when posting and signing up. The reason I did not sign up earlier is because I was told it was censored and useless which it is. But it is a little less useless than the rest of them and at least Reddit tell you that they are removing your content instead of simply hiding it.