When I first started I was the 7 to 8 minute writer. When my stories become more personal I hit around 5 to 6 minutes. However, my more inspirational works fall around 3-4 minutes. For me it depends on the topic. A highly researched piece is going to fall into the 7 to 8 minute range. And a personal story takes me about 1,000 to 1200 words. But what performs best are my 3 to 5 minute pieces here on Medium.