Rocketthemes and Grav

Hi all, I’m reasonably new to Grav - but I really like the concept of a simple Markup-enabled DBless CMS. I’ve been trying to set up a site with a Rockettheme Theme, as it was recommended on a Grav page. I’ve got a say the whole experience has been kind of messy. Having to install Gantry which seems like something optimised for Joomla and then using that instead of Grav’s content management tools seems to subvert the purpose of Grav. All the content is in the front matter and not editable in the Pages of Grav’s admin.

My quesiton is - do I have to use Gantry with these themes? Is there a way they could be better integrated and usable with Grav’s built in tools?