MongoDB is required to be up and running and a Yeoman generator is used to generate the application. Although the prompt based start-up in the command line helps you a lot, it still can be hard for someone inexperienced with NPM and Yeoman.
Con It's hard for front-end developers with no MVC experience setting up views
Keystone follows MVC practices in managing routes, views and templates. Back-end developers with experience in working with MVC frameworks will find themselves at ease since the beginning, but developers who work on the front-end only will have a hard time finding what they are supposed to do to set up templates and such.