Just be sure to put a lot of care into your product listings. Everything from the titles you use, to how effective the description is at convincing potential buyers your product is better than the rest, and even taking care to shoot high quality product photos can have a dramatic impact on your sales. I recommend using photo editing tools like Fotor, which gives you the ability to edit your images, create captivating graphic designs and more.
Good list. Some definitely good examples, if people really want to try. I think “interview other people and sell the interviews” will work the best. Or just build a website and post those interviews. I have managed a few websites where we interviewed people and those get a lot of visits from Google searches. For anyone out there willing to interview people I would recommend it, it will make you money.