There's something I've been thinking about for a while, regarding the map borders. That big Reddit leak mentioned that the game spanned 5 zones, which would likely be the states/territories(also, he'd apparently confirmed the map's validity). Now for the longest time, I couldn't find a decent way to split up the map evenly, while still having it make sense geographically. I was thinking that he may have been incorrect in what he remembered, or just had outdated info. The main issue, was that West Elizabeth just seemed to small to be it's own state. I now believe that's because what was in RDR was just part of West Elizabeth. One of the first things I noticed while playing around with boundary colors, was that Big Valley was almost the same shade as W.E. Most other districts had distinctly different shades with those they bordered. Now this may just be attributed to terrain similarities, but there doesn't seem to be much of that if you look at where The Heartlands and Scarlett Meadows meet. I think Big Valley is the rest of West Elizabeth, and there is a decent amount of evidence in the first game to support this. User RedDeadRenegade actually made a post about this same thing on the Sub-Reddit, and along with the same conclusions I made, found some additional evidence that I'd never picked up on, so I'll just let him explain:
"While scouring over the leaked RDR II map, a thought came across my mind. For those who don't know, the West Elizabeth area from RDR will be returning in the new game. It occurred to me that it's never explicitly stated that Tall Trees and Great Plains are the only areas in the state of West Elizabeth. It always struck me as odd that a state big enough to have its own governor only had one town in it.
So, maybe its possible that some of the new areas will still technically be within the state of West Elizabeth, but just areas we couldn't see in RDR. Like the "Big Valley" area on the new map could fall under West Elizabeth's jurisdiction. I think that would make sense because they look to have similar terrain. I also say this because in RDR, Nastas says that some of the Natives from the local reservation are turning to Dutch. He specifically says local implying its within the state. But there isn't any reservation you can find within the map. Well, on the Big Valley area of the leaked map (which is directly north of the Tall Trees/Great Plains area, and even shares a land border) there's a place called "Painted Sky" which sounds like the name of a reservation to me. In one of the RDR newspapers, they also mention Dutch killing two guys at a homestead "just north" of Blackwater. Well, on the leaked map, there's a homestead directly north of Blackwater. It would make a lot of sense that they were in the same state, especially because the newspaper was reporting on it like it was a local issue. This all makes me think that the state of West Elizabeth is bigger than what we saw in RDR, and that new parts of the map in RDR II will be considered a part of West Elizabeth. Just speculation of course."
What we concluded was that there's no way Dutch's gang operated out of a state that has literally one town/bank. Now as for the rest of the map, this made things wayyy easier to dissect. What helped even more was trying to interpret what states/locations R* is trying to interpret with each district. I think I've narrowed it down to just 2 variations. The first makes more sense in terms of land mass, and also if each zone will be it's own state. However, I feel like states continuing across that big of a river is a bit far-fetched. The second makes more sense geographically, and from a game-play standpoint, but the shape and location of some boundary lines seems odd.
States Variation 1
States Variation 2
As for the island, I think it might just be another North Yankton, or will simply be included in whatever zone you use to access it.
Edit: I've updated the maps with new info...