Thanks for you questions!
I had/have several channels in different niches. From internet marketing product reviews, over prepper stuff, paleo diet to gaming videos.
I had screen capture videos, videos with my chubby face in it, sales videos that I was allowed to use, whiteboard videos. I tested a lot.
When it comes to making sales by putting an affiliate under a related video, you have to go for the big commissions, that what I have learned in the past. Take a look what kind of affiliate programs pay the most for a lead and make a related video.
The best videos are those, where people see, that you are a real person. All those fancy animated videos and stuff does not convert that well. I will make a post about how to rank videos in the near future. I planned to sell this a course, but atm I have not time to set up the whole sales funnel. So I will put it up here. :)
Hope my comment helps so far.