I can think of some products that aren't "out there" (to the best of my knowledge), but that I'd like to see someone manufacture and sell.
A certified lead free, made in the US atomizer for one, high quality that lasts a long time, and/or one that can easily be rebuilt - like the hellomizer would have been if the project hadn't been scraped, but maybe a bit smaller or at least one that can be used with cartridges as well as drip tips.
A metal (aluminum, stainless steel, or titanium) cartridge, one that doesn't melt regardless of failure to index, and that can be re-filled and reused indefinitely. Preferably one that has a flared end so that a drip tip could be used with it as well (just for aesthetics or the shape) or that itself is shaped like a contoured drip tip.
Any flavored or unflavored ejuices made from the ground up in the USA, including the nicotine being made or extracted here.