#2 - No mention of research done. What is your demand? Competition? Commercial intention? If you truly do it right, what are the actual numbers you came to to justify your niche?
#3 - Has their been a discussion on how you will sell your product? I don't mean on what platform, or your marketing strategy. What I'm referring to is: "What is going to set you apart from everyone else that is selling this product? It's not the product - not even the price that matters. What matters is how you sell it. It's hard to have an original idea on the Internet. 65 million-billion-infinity people are selling your product online. But why will they buy from you?
#4 - With selling on eBay, or anywhere else, what is the market worth? Are you assuming that you'd sell your items at the MSRP? If so, nothing ever in the history of the universe has something sold for the MSRP. People buy it for the perceived MARKET worth of the item.
#5 - How much are you making per sale? This cannot, and should not be assumed/guessed. Even worse, it cannot be given to you buy a supplier. I often see this from suppliers: "Your cost is this, you sell it for this, you'll make this much!" (The worst offender, and supplier, is Doba. There are many like it, but Doba is a cancer.) However, they never tell you what the fees are - shipping, eBay, Paypal, Dropship fees, etc. When calculating all of them fairly, you'll often see that you're taking a loss.