All the advice on this page is really worth reading over a few times and the videos are terrific!
So for a thumbnail splash image, I enclosed an idea, below. I don't think that a picture of a silk moth is capturing the essence of what you're video is about, but it'd make a wonderful logo icon. Since you are Crowing Hen, why not get a hen sitting on the sheep's head or something? Who can resist animals???
Since everything is fine the way it is (it is), I'm guessing that what you need is to put your logo onto all the fiber and weaving and spinning sites. Then those who already have a similar interest will be most likely to click on your logo! Try homesteading sites too. Also include more how-tos for making things. "In this online workshop we'll be weaving roller blinds in the traditional Scandinavian way with a scalable size pattern downloadable HERE!" Then you could advance to PayPal lessons or whatnot.