Using GroupJive Group as a Community

Our business allows creation of Private and Public communities. We plan to use GroupJive Groups for this purpose. Each GroupJive Group will be a "Community" of members who could be invited or could join the Community. 
Is there anything I should keep in mind with this approach?

Is it possible to have Community owners be assigned to the Special Group automatically, so we can display appropriate menu items to the 'Special' group?
 

Is there anything I should keep in mind with this approach?

Nope, sounds like standard out of the box usage of CB GroupJive. I'd personally forgo using the Files, Videos, Photos, and Wall integrations in favor of CB Activity and CB Gallery integrations though as the provide more modernized features. Those old plugins will eventually go away and require CB Activity and CB Gallery for stream and media sharing features.

Is it possible to have Community owners be assigned to the Special Group automatically, so we can display appropriate menu items to the 'Special' group?

You can assign a custom usergroup to users whom have created a group using CB Auto Actions. The gj_onAfterCreateGroup trigger is fired anytime a group is created and using the Usergroups auto action you can easily assign a usergroup to users on that trigger.

In the attached image the CB GroupJive plugin shows Integrations with CB Activity only.
Does this mean that CB Gallery is not integrated? If yes, then how is to be integrated with GroupJive?
Is CB Gallery automatically (internally) integrated with GroupJive/

CB Gallery is integrated through CB Auto Actions. Within CB Auto Actions > System Actions publish the "CB Groupjive - Gallery" system action for integration of CB Gallery into CB GroupJive. In a future release this will just be built in like CB Activity is.

with reference to your response:
"Nope, sounds like standard out of the box usage of CB GroupJive. I'd personally forgo using the Files, Videos, Photos, and Wall integrations in favor of CB Activity and CB Gallery integrations though as the provide more modernized features. Those old plugins will eventually go away and require CB Activity and CB Gallery for stream and media sharing features."

We are reinstalling CB on a new server.
If CB Activity and CB Gallery integrations can provide the functionality, do we still need to install the Files, Videos, Photos and Wall plugins? 

If CB Activity and CB Gallery integrations can provide the functionality, do we still need to install the Files, Videos, Photos and Wall plugins?

No, you can forgo installing the Files, Videos, Photos, and Wall integrations in favor of using CB Activity and CB Gallery. CB Activity provides activity stream integration replacing the Wall integration. CB Gallery provides a full multi-media gallery and replaces Files, Videos, and Photos entirely.