While there is no way to clone a group space, you can copy home page layouts from one group to another.
The "Copy To" and "Copy From" buttons at the upper-right of the group space allows the customized element layout of one group to be applied to another group's pages. Once an admin has setup their columns and elements, they can click one of these buttons and select one or more of their other groups. The dashboard settings from the source group will be copied to or from the destination group(s). Any existing customization on the destination group(s) will be overwritten. This can also be used to pull forward a home page setup from an archived class!
Copying a dashboard layout will copy both the content from within dashboard elements as well as their arrangement on the home page. Elements tied to group features (e.g., Calendar, Media, Bulletins, Resources) will populate with the corresponding content from the group itself.