Excellent post! Thanks for writing about comments, because I think many Steemians undervalue them. I went through a similar process when I decided not to use bidbots, just over a month ago. I decided to take a more strategic approach to Steemit, using community building etc, and it is definitely working - slowly and gradually, which in my opinion is always the best way, as overnight success is often followed by overnight failure!
Part of this strategic approach was to take a look at my Steemit "accounts", and like you, I was astonished at how much my comments had netted me - not a fortune, but significant enough. I'm quite a blether, and an opinionated one too, so I tend to enjoy writing comments when I have the time!
Also, when you're focusing on bidbots you tend to neglect alternative ways of making a splash on Steemit, so you're missing out on some important lessons!