It would be great if there was the feature to sell posts to authors. Users should be able to purchase any plan that will give access to posts creations for specific post types. For example, a user buys the 3 posts plan and have access to create 3 posts. Then he can buy the 1 post plan and create another post, or buy a plan with unlimited posts but in limited time. Like the websites that sell listings and users can buy the amount of listings they need to create.