I found the default size of the WooCommerce shopping cart icon (in the Storefront theme) was a bit on the small size.
The icon is textual and comes from Font Awesome. Normally, this would be an easy change by adding fa-2x or something similar to the style declaration. Inspecting the CSS in Chrome didn’t offer me such an option (I’m new to Font Awesome) so I added this CSS to the custom CSS in my Storefront child theme:
/* Increase size of shopping cart icon */The 1.25em increased the size of the cart icon to better reflect the size of the menu text and stand out better.
font-size: 1.25em !important;