Sometimes in the pursuit of attracting more subs we forget that our followers commenting and faving our works are individuals themeselves. Some are artists, others are fans. I think we should, more often, really take time to appreciate our subscribers. At the time of writing I have about 20 followers. For many, that's only 20. But for me I think, wow... there are 20 people I've never met before trusting me with their time and attention. They have lives, ambitions, and cultures that I have a chance to leave an impact on, even if its just scribbles.
Whether you have 5 subs or 5000, I think it's important to cherish each one. Not as a collective, but as individual people. Maybe you don't have the time to reply to every comment. I think the simple act of taking time and thinking about the person following you and the connection you've made with them is worth the "productivity time".