Hello, for me creating a own cart page with Cart contents loop is a best practice and more flexibility than use bricks widgets for cart page. It would be great to add similar functionality to the checkout page and dropdown menu for the mini cart.
That is, to place an order, we could add a brick form, add the necessary classes, attributes and fields so that the plugin can correctly register the order, as well as the necessary fields for displaying the delivery method, the list of goods (you can use the basket cycle as a template), output methods payment and all this through similar dynamic tags.
For the mini cart widget, everything is the same as for the cart page, only in this case we get more flexibility, we can turn this into the functionality of some plugins for quick checkout without going to certain pages. That is, we can create a step-by-step form, where at the first step we have a basket, then data for delivery and payment.