The first thing I would do is get rid of all the Medieval villages.
Damn, I knew I was forgetting something important!
Re, the workings of the stargates, sure, that can be modified. I'm sure the fine tradition of having the gates break down when the story demands it can be continued.
But the details of how the gates work is not what I think of as the premise. The premise is their existence and that they threaten Earth because there are critters out there who are powerful and use humans as hosts. So what do people do about that?
But mixing gates and ships sounds like it would increase the production budget substantially, and might be a nonstarter on that basis. Maybe save the ships and shuttles for stories where they are essential, and to provide some different settings.