Absolutely incredible. This is one of my favorite renovations so far.
You saved an old trailer and made it a masterpiece.
As for a portable toilet there is no better option than the Thetford Curve.
I ditched the original 10 gallon porcelain marine toilet in my Scamp
16 for the Curve and I couldn't be happier. Saves water, allows me to carry an extra 2.5 Gallons since it has it's own fresh tank, I can empty it anywhere for free, and it's comfy!
Better yet the space saved allowed me to build a bathtub where the old toilet was. I simply remove the toilet from the tub when I want to take a bath.
I think it would work nicely for you along with a small tent for it that you could set up under your awning
Again, AMAZING renovation of that trailer. No criticism here!
It really looks like a brand new factory job on a modern (and expensive) trailer. Impressive.