We were there in July, and we walked the entire pathway from the farthest out cabins (8001 on the north side, 8026 on the south). There is abundant landscaping along the entire way, and I can tell you that the farthest out cabin is 8026--that is located on the side nearest FW, btw. Yes, those cabins are what I would call reclusive, roughly 8020 through 8026. From 8026, the hike back to the main Lodge is easily 300 yards or more. 8001 on the other side isn't quite so far, but it's still quite a haul. To my knowledge, there are currently no golf carts or Segways available. You can rent bikes at WL, however, so that might be an option. The cabins actually have some space between them, but the landscaping and vegetation is still in its early stages of growth, so you can definitely see your neighbors. I'm unsure of the sanitation system noise, but I would guess that boat horns could be an issue for some, especially if you get one of the cabins on the north side (closest to MK) since those along the waterway between WL and MK. I will say that although the walk from the farthest out cabins on either side is lengthy, given the relativity to how much one walks at Disney anyway, that it wouldn't be an issue for us.
Unsure on how many rooms are left to the main Lodge, but you can get a good count on the
DVC rooms by checking the diagrams on page one supplied by
grandcalifornian.