Ability to create new roles within the Add User function

I often need to add a large number of new users at a time. It is very time consuming, and I don't know if their role exists unless I have a separate screen open to search the roles, and then add new roles if needed.
It would be a big time saver if I could do this within the Add User screen, where I could click on "Add Role/Responsibility" and if the role isn't available, I could have the option to add a new one and assign to that new user from the same screen, rather than having to close the add user screen, go to the add role screen, add the role then go back to the user I had just created to assign it.