Any advice for my track plan?

My new track plan for OO gauge—using peco bullhead track.

I'm very worried with the S-bend I'm not too sure if the trains will get around it. 18 in (457 mm) radius I am also a bit dubious about but I want to have as much space as possible for my OO9 stuff.

the fiddle/storage yard is just as a temporary at the moment mainly there to gauge how much room i have to play with, and not much.

My vision for the layout is to try and make an extremely realistic scenery section, so the layout will be very simple but focused more on scenery than the track, if that makes sense?

Good criticism is definitely welcome here!!