Before reading the list bullets I read the first sentence and last sentence. I found the first ten things that came to my mind in your list. I am sitting here pretending like I might compliment the list by offering something you missed and I'm coming up short. I will have to actually step back and brainstorm. Which I find quite nice, actually. Thanks for sharing your research!
One of the groups of products I sell fits all of these exactly except "low dominance of existing competitors." The way I have gotten around that is to find/create a subniche. This group of products is what I expect to keep on selling indefinitely. They are all those things on your great list and for me, fun and interesting too.
One thing I think is ideal is the capacity to produce the widget yourself with little investment of materials or property, mostly just skill. Skill makes it difficult for others to make, and you don't have to worry much about the supply route or variations in currency when you make it yourself.
I think the idea of it being small and light is excellent and key for the future of increasing energy costs. Cool list!
Yeah, the 'small and light' part is where I blew it... Most of my stuff averages 60". Giant pain in the a**. But then, ten years ago I had no idea I'd be doing this full-time.
I would love to focus on just one segment of what I do, which is stuff that is much smaller and easier to make. But the profits are way lower. I'd have to sell 6 times the volume to be able to cut out the big stuff.
Vertical integration means going further down/up the supply chain. So maybe you start by drop shipping, then you start buying direct from the factory, then you build your own factory. Or you sell to other retailers, who then sell to the consumer. Eventually you cut out other retailers, and become the end retailer yourself.
Web hosting is an extremely competitive service and suffers from a very high risk of obsolescence as more powerful servers, speed and technology come in apart from new versions of operating systems and cheaper bandwidth.
This bit of humor will likely get nuked... then again, perhaps not: as described list above screams razor blades or condoms... small, light, durable, easy to produce and ship, with a long shelf life. I've been looking for products like that for years!
Biggest problem is finding NEW PRODUCTS (there aren't any), which are not sad versions of what already exist, or do not have a higher cost/expense than existing inventories... said cost which kills potential profits.