Here are some pictures from our rig and a few thoughts as you ponder your next move..
From the looks of things the WH and toilet locations in your rig are in, or very near the stock locations. The WH is normally enclosed with insulating material and in our case a sheet metal box. The fact that yours has none probably gives you more room than usual. You can see by the pictures that there's not much room. On ours I'm guessing that there's no more than an 1.5" between the WH and the divide, and maybe that much from the divide to the toilet. Definitely close.
Certainly things can be moved to suit your application but there are some things to consider. Moving the WH means you'll most likely need to patch, enlarge, or otherwise deal with the shell penetration. I considered it but decided to forgo that idea. There are some other options such tankless units, no WH at all, and I've seen some owners install small household electric units. There are pros and cons to each application.
As for the toilet, it empties directly into the black tank. So relocation means relocation of the tank, a new tank, fitting relocation, or some funky plumbing changes. This is something to consider if you're ripping a large section of the floor out and have the means and methods at your disposal. Plumbing the black tank drain and maintaining weight distribution would then be your other considerations. And there are alternatives in the world of RV toilets as well. You might contact 87MH and see what he did with his 78 Sovereign
. He created some more room by rotating the toilet and removing a portion of the hallway wall.
I encourage you to go the path you feel works the best for your application, and by all means be creative. Think outside of the bowl..err I mean box,and show us your good ideas so we can copy them.
Best of luck,