I would agree that if a channel has a small number of views and that it would take a year or two to hit that $100 payout threshold, why bother. I would recommend being ad-free as much as possible to try to entice more viewers to watch your videos. If a video starts to gain traction, monetize that video.
As for Fullscreen, I am separated from them. I had over 900 videos and they mass-monetized all of my videos in violation of our agreement. I was told that I could message them with the titles and URL's of the videos and include which monetization setting I desired. I had over 900 videos at the time and I'm not going to waste more time with them. Now that I am separated, I will do the adjusting myself.