Interesting, different and definitely ambitious. Some things to consider though.
1. If it's a manual rotating monitor on a bartop, can you not do something where you can just quickly pull it out, re-orient and put it back in*? A few projects back in the stone age had the "rotating mechanism sticking out the side" setup and it always looked really, really awkward. It was something new back then but now it seems like there are better solutions.
2. Why does it even need to fold, if I may ask? It seems like the idea of folding it is neat but it makes the depth and lines a little kooky (ex. the excess space in front on the controller.) I constructively criticism without a better solution I admit but if storing a bartop is a concern, then maybe just make a control panel separate from the body that can store neatly inside of it or something similar.
Good luck!
*"That's what she said."
I thought of using a hinge on the side, where one could open, rotate and close, but I didn't really like that idea. I thought of putting in a small motor but I don't think that would work with a notebook power supply. Are there any other solutions that might work?
Folding just for space (it fits on my breakfast bar I don't use) and for easy transport. I could put a trackball or spinner to take up space so that the control panel doesn't look so large. I would like to play DOT...
Is there enough clearence there for the joystick?
There should be. When I build it

might have to make a modification.
Any chance to ditch the CP and add a second LCD for pinball? CP on the nub of the cabinet?
Interesting idea, the control panel is large enough to fit a monitor, I'm more for shooters, and fighting games than pinball.