One thing missing, a low priced durable tube mod. Something like a roughstack.
Also, you've named a lot of things that might get people there but, you need something to keep them coming back. Juice can help with that but, here are some suggestions.
DIY supplies - Everyone has some kind of bottles but, few carry things like graduated cylinders. Try to have some hard to find items in this area. A good line of flavors will help too.
A good selection of cartomizers and atomizers. Don't just stick to 510 or 808. Some good adapters to go along with this. Someone might decide they want to try something a little different. To get their business, you'll need to sell both the adapter and atomizer/cartomizer.
Generic batteries and chargers. I think this is the way things are going. Best to be ready for it.
Assuming you get established, start looking into mod parts. Madvapes is all by itself in this area and they are just about everyone's goto supplier.
Stay on the hunt for new and unique items. Make your site the one to come to for new stuff.
Keep your prices fair. Ship quick and make customer service your top priority.