Hmmm.... Mirror... Not sure. I actually like the bridge straddling the yard as it does rather than at one end of the layout as a trick to hide the mirror.
I may have to play a bit with the bridge to see how it looks at the end with a mirror.
The yard office is a Walthers modulars bash:
The bridge is a pair of Rix early overpasses, and the diesel shop is 1 and 3/4 Walthers car shops. And everyone should recognize the tried and true Atlas switch tower as a stand-in for DAY tower. That's a Walthers water tank which isn't too far off from a standard PRR steel water tower.
No way to turn a loco. That's not great, but a turntable is such a hog (especially one that could turn an M1 with 210F75 tender).