If the default email template of WooCommerce looks plain to you, and you are looking for a way to customize WooCommerce emails, here is what you need. WooCommerce Email Template Customizer is a helpful tool that helps you build and customize WooCommerce emails.
The plugin provides sufficient basic elements and WooCommerce elements as well as developmental tools for users to build a complete email. You can easily drag and drop, edit, and customize the layouts/contents inside the email templates with no coding knowledge required.