How could I obtain a list of all users within CM?

We do not have a reporting option for user data within the UI - but you can use the API to obtain the user information and whether they are Admins/CMAdmin/Users. We have some information on the process here to outline how to obtain this information as needed. Unfortunately, this will only be able to designate the Admin/CmAdmin/User status - we do not have a method for obtaining the roles held by all users within the system.

For obtaining all users, you can use a call like this: /api/v1/users?fields=name,role,username,id

The API is limited to returning 100 records at a time; but you can use the skip function to obtain the next 100 by adding &limit=100&skip=101 and increasing the value as needed. You can then use a convertor tool such as this: https://www.convertcsv.com/json-to-csv.htm to take the JSON data and convert that into a CSV file.