In 2013 Alex Turnbull from Groove wrote a post about what's made Groove's content marketing strategy so successful (The post is actually titled "How We Grew Our Blog to 5,000+ Subscribers in Five Weeks"). One of the things he mentions that they did right (though not initially—they've learned from mistakes, too) was finding a unique angle for their content.
This is a companion discussion topic for the original entry at https://blog.ghost.org/focus/