Hi gangward!
Before switching to another ecommerce plugin, I highly encourage you to optimize your site’s performance to see if it helps (I really think it will). You can use tools like GTMetrix to identify what slows down your site, and find ways on how you can speed it up.
A few things you can do are:
1. Optimize your images to reduce your page’s size even further. This can be done by deleting unnecessary data like the date the photo was taken..etc.
2. Minify your CSS and JS files, get rid of white space so they load faster.
3. Combine all your CSS files into a single document to reduce the number of requests. Same with JS.
There’re plugins that help you do all those with ease. The two I recommend are Smush for image optimization and Autoptimize for CSS and JS optimization.
There are a few other ways that are a bit more technical to speed up your site even further, like adding expires headers (saving resources on browsers so it loads way faster the 2nd time the page is visited by a user) and using CDN (for consistent load speed in multiple locations).
Let me know if you need help with anything I mentioned.
– Said