From my experience, Yoast SEO is the best tool I've used for my Shopify stores.

Shopify automatically handles trailing slashes by redirecting URLs with a trailing slash to the corresponding URL without it.  This should not negatively impact your SEO or rankings.  Just ensure that your 301 redirects are correctly set up from the ...

You can consider upgrading to a premium Shopify theme such as "Turbo" by Out of the Sandbox or "Prestige" by Maestrooo. These themes are known for their speed, advanced design features, better navigation, and enhanced SEO capabilities. To transition ...