Ive started developing magento2 and the cli tool is very nice and easy to use.
But I was missing some tools for code generation like modules and themes.
Everytime you create a module or theme you have to create the same boilerplate registration.php, module.xml and other config files.
For example to create a new module:
php bin/magento module:create Vendor ModuleName
This code could be generated through the CLI tool.
A good example is the @angular/cli tool for Angular.