Think about the last thing you made that fell flat. When you created it, did you have a particular person in mind who would especially appreciate and benefit from that work? Or maybe a group of people?
Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius — and a lot of courage — to move in the opposite direction.
Once you have hypotheses for who is successful and why they are successful, you can hypothesize possible adjacent users segments. This will involve changing one or more of the vectors that you identified.