Sometimes a simple reminder can spur a sale. If you have repeat customers that log into your commerce site, you may be able to remind them if they did not complete a checkout.
You don't need a new website. You need to make your current website more effective!
How can you do that? There is no single answer -- websites are part of a larger system, and you need to consider many different aspects to make your site effective.
We've been making websites since the start of the web, and know what makes them work -- as well as not work. Take what we have learned to make your site better!