I just solved my own problem. So by this point, I had been posting on Instagram daily for 1 year, and wanted to increase my following. I heard that the way to do well on social networks is to... well... BE SOCIAL!
The problem with Instagram is that it was painfully slow to "be social" at scale using the existing user interface. And I did not want to use bots to grow, as I've tried it and it felt inauthentic.
I then got the idea of mixing something like Tinder, and Instagram, to make an interface that displays the latest post of people in your niche, so that you can easily engage on their post with a comment.
Think: Gary Vee's Dollar Eighty strategy (if you don't know, Google it)