The screen experience you have indicated is not possible via an Add-On. If you wanted to change the creation experience, you could create an application and collect similar inputs and create the group in-lieu of this experience though. You would simply promote that link in the navigation menus and around the site to insure that it called. See: App Action Contribution Reference for some ideas of where / how you could link to this experience. Hope this helps.
Thanks for the information Ryan.
So would you recommend using the approach you detailed, or using a plugin, to achieve this?