I started on Etsy, offering mostly ACEOs and those have done well. I take nothing away from my ACEOs as I am very proud and very pleased with the ones I have painted. They take me longer than one would think...just because they're smaller doesn't mean they're easier to paint.
It is probably easier, for me anyway, to paint on larger surfaces. I think they 'translate' better in photos and they are certainly easier to see.
Look for, at least, one new painting...some on canvas sheets and some on prestretched canvas...every week.