Hello,
Thank you for contacting us.
1. The DOM size corresponds to the number of elements on your page. So to reduce the DOM size you would need to remove unnecessary images, products, posts, menu items, and so on. Our theme has only one CSS file and each page loads only those JS files that are required for the current page. Other JS and CSS files are not related to our theme. We are also working on this for our next update and will reduce the JS and CSS files more.
2. Sorry, but there is no such option in our theme and WooCommerce by default. It may require additional code customization or extra plugin but we don’t have an instruction for this. It is out of our theme support scope.
Regards