Any simple way to completely remove checkout and use only checkout with paypal express from view cart page?
As far as I can see, buttons with the links to checkout exist on 3 templates only:
Cart page:
design\themes\responsive\templates\views\checkout\components\cart_content.tpl
Add to cart notification:
design\themes\responsive\templates\views\checkout\components\product_notification.tpl
Cart content block:
design\themes\responsive\templates\blocks\cart_content.tpl
So you can disable them to solve your issue