Try adding catching calls to action written in large font with some bright background. People here say they put large calls to action right in the middle of their pictures as a kind of a strap that catches user's attention, an it really works for them (besides, it is quite easy to automate using Photoshop automation or any other similar means).
If you can get CTR 1% from all your pin impressions, then I could say it's already showing you have a good pin image that makes people want to click it on your website. My recommendation to increase the number of clicks will be to improve your pin image and more pinning (pin quantity). Regarding your pin image see what you can improve from the text content, pin image, and colors to make the audience stop scrolling and click your pin.
