First of all, I really think you've done a good job building your site so far. It loads quickly, it's easy to navigate, and you do a good job marketing the product through your sales copy.
The key component I think you should focus on is the original product content. Such as product photography, DIY tutorial video, .gif video of how to use, etc.
Video and social proof will go a long way to further engage your visitors into taking action to purchase the product. We have a guide here that will show you how to leverage social proof to boost your brands' authority and reputation.
In fact, there is a useful help guide that focuses on succeeding with single-product stores. I definitely recommend giving this a read through to generate more ideas.
Let me know if this helps! If there is anything else I can help you with, please let me know.