I originally put this in the battle grounds and dueling forum but not a lot of people go to that forum. But, here is the link if you want to see the original post.
https://forums.elderscrollsonline.com/en/discussion/491420/group-dueling#latest
The basic idea is that a simple way to add new PVP content would be to allow group dueling. People really want a battleground with just two sides. The easiest way to make this happen is allow the group leader of one group be able to challenge the group leader of another group to a duel. No need to create new maps because you could do this anywhere. The only requirement should be the two groups have to be the same size. So 2v2, 4v4, 8v8, etc.