Questions re User Roles

Hi there,
I’m currently looking into User and Role Management for a customer of mine and have two questions:
1.) It seems that there is no way to delete a custom role once created and saved. At least not via the UI. Is this correct?
2.) When creating a new (i.e. custom) user role, I would like to pick an existing one, clone it and then use this copy as a basis for changes, e.g. to add or remove specific permissions items. It seem that this is not possible, but I have to start from scratch. Is this correct? If so, how can I see how an existing standard role is configured?
Can I leverage the API for help with both items? Or would deletion of a custom role require a request to the Support Team?
Is it worth submitting feature requests for both?