Most Welcome,

I’m glad that you enjoy our support and theme as well. :-)

The best way to detect that which plugin is not good for the site performance. You need to disable the third party plugins one by one and then check your site. In this way you will find that specific plugin which is the cause of the slow speed.

Also not only the plugins which makes your site slow. It also the content you have added to your website. You already have WP Super Cache which is a good plugin for better performance. Also the site speed depends on the hosting service.

Sometimes websites load slowly because of the server when you are on a low quality hosting service that’s why the speed is slow.

Best Regards.