Starting up an ecommerce site alongside Ebay is the right thing to do long term but it won't compare with Ebay for sales initially or even ever. Everyone likes to moan about Ebay but they do a fantastic job of getting customers to buy your product.
Your long term goal should be to try to get your customers to use your online shop instead of Ebay which can be achieved by including a leaflet with every order plugging your online shop. You should also offer loyalty discount codes to encourage shoppers to use your online shop instead.
Longterm, this is the way to go but don't expect instant results unless you plough money into your own marketing. Think of the Ebay costs as your marketing costs.
I hope this helps