Years ago, we built an elevator prop similar to yours but with way less detail. We did 2 things different that you may want to incorporate into your build if you can as it got the most reactions.
First, we had an actor that ran the elevator. When the people went in, there was only one way in and one way out, not two. After they were locked in and the ride started the actor pulled a swing wall which changed the path once they were out and the people honestly thought they were getting off at a new location because they went out the same door and were directed differently than when they went in. We even decorated the back of the swing door to match a new decor design for the room they were entering. That made it even more confusing as nothing looked the same.
Second, we had a steel plate on the outside of the elevator that we hit with some angle iron when the elevator was falling. You could automate this with a cylinder. This loud metal clack is ridiculously effective at a scary noise for the people inside.
Seriously great work on the elevator. I wish I had thought of half of the details you did.