Yeah, the file's basically quadrupled in size now, sorry to say. But it's with good reason, because we now have some cars on the road!
Now instead of an empty road with abhorrent sightlines, we have an almost L4D looking road with surprisingly short sight lines (I blocked the worst one, and the rest are actually okay. The curve of the dam and the towers does more work than you'd expect).
It's still a little rough perhaps, but most importantly I think it greatly improves gameplay up top.
Some props were also added to the middle path's rooms to help with sightlines there. They're still a bit long for my liking but they are much better.
Overall, I am still experimenting a lot with the layout, but I think the top mostly looks good at least. Also there's HDR now, though it doesn't make a huge difference.
Maybe I'll do another map test? Maybe.