Why can I create more than one Acquia Cohesion template for the full view mode?
You can create more than one template to provide layout and style alternatives with the use of the template selector.
Acquia Cohesion renames to Site Studio from version 6.2. Tell me more.
Yes, you can personalize content within Acquia Cohesion using the context module.
No, the entity browser does not work for component defaults as the entities are content, not config.