Fantastic effort thankyou. I'm not sure of there is already a workaround, but one of the things I noticed is that I'm a little too tall (6 feet) to play some of the machines up close without the marquee getting in the way of my vision.
It would be great to be able to scale the room size or the cabinets to suit individual height of player. Perhaps a temporary hack might be to set the quest floor level a little higher, this might sink me into the floor a little, not sure as haven't tested that idea yet.
Lastly, do you have any plans to add a shader for scanlines? I think that would really help add to the realism if the quest is up to the task performance wise. Some additional CRT effects might also be nice down the track, bloom, RGB colour distortion etc, you are no doubt aware of this but thought I'd mention it, https://docs.libretro.com/shader/crt/
Edit: I just noticed you have a damage shader already that has CRT effects... I'll check it out.