Haha, what an excellent idea, plus a hybrid will be even uglier!
Having a removable CP on top of the screen would be relatively easy.
Finding a good solution for pinball buttons and speakers is more challenging.
So MAME layouts work well for the marquees, how about other emulators, are there any relatively simple way to have something displayed for them?
One image per system would be enough. Worst case, a single image for all none-mame emulators would work, too.
(The attached model has a 23" 16:9 and 17" 4:3 monitors..)