Modeling a Model Railroad - Backdrop

It took some time to find a piece of styrene that I could bend enough of to fit the curve but there it was under another pile of styrene sheets. Of course as I tried to fit this in I realized that some how I had managed to torque the whole thing out of square. I think that when I start actual construction that I need another cross member  at the top, in fact I'm not sure why the original design doesn't have a cross piece there already. I also need to keep in mind that the particular PVC sheet that I'm using is bit bendy which will not be the case with wood, but would that be an issue if I try to build the benchwork out of blue insulation foam?

Backdrop in place but untrimmed

A look from the top along with all the markings from the project that it was originally for.

Trimmed up, more or less. It could be a bit neater.

Backdrop in place, note that the benchwork has been notched out for the creek bed.

Now its time to put it together, temporarily anyway, and its still a bit out of square at this point. But its not looking to bad and precision is not totally necessary at this point (unlike when I build the full size modules).

Looking down to see the tracks in place. I have not glued this in yet. A few clamps to hold things together and overcome the slight twist that still exists.

This is the view angle I'm going for, although even a little higher might be better.

Here are the buildings along the back siding in place along with the viaduct on the right.

And a closer to the actual viewing angle. The question is; does this feel claustrophobic? Do I need to increase the height of the supports to increase the distance between the roof lines and the backdrop curve?