Could you consider make the App/Config directory more compact, optionally expanded or rewritten?
For example:
Make Config/Mimes.php have default values follows the frame-system directory, if we want to modify it in our application, we can add a new Mimes.php file to App/Config for extend or rewrite.
Because we do not need the custom config of Mimes in most cases, and many of other config files.
This will make the App directory more compact, do you support this idea?