Anything could be game of thrones (early seasons) if it well written. You don't really need any Halo rights if you have good writers and can make a good show. The point of having Halo rights is they let you produce a mid show but have an automatic audience.
It seems that way, but it's not that easy. Starcraft competitions are still on tv in South Korea 28 years later because they got the balance just right, and all the dirty little details of that universe.
In theory you can make any sci fi show about future humans and a couple other species going to war. Should be straightforward.
But getting the balance of that universe right in terms of little details is tricky: Halo has done the heavy lifting already.