gPanel is able to put a lot of often-used features in the places they just make sense. There is a lot of power given to you, where you'd need to sign in as a user if you only have Google Admin at your disposal

This tool lets you access all of your google administration needs in one place. Users, Groups, Resources and Sites. I like that you can see which individual is in each group, which group has which user in it, who can access resource calendars and the ownership of all of the above.

They have a lot of reports that can help to understand usage, or help with compliance with rules or policies. You can easily browse other users data, and change permission or owner on files. Imagine you have an employee out for a month, and the project needs to go. You may have a manager asking access to a very important files that the employee was working on. You can set "Rules" for monitoring, like "files shared outside of the company" with some actions, like "need approval". May be useful