Redo, the 3rd and 4th player sticks should not be angled. Period. Every beginner makes that mistake. They should face north like the other sticks do. Some little part of your brain is thinking about gamepads and thinks they should be angled and you probably even saw pictures of a few machines people built where they did that. It is wrong, wrong, wrong. If you angle your sticks the whole thing is ruined. I am sure some helpful person will chime in and argue that THEIR angled sticks are awesome. But that person is wrong. Original machines didn't angle them, not even gauntlet where you would actually stand all the way on the side of the panel.
The 7 button combined Neo Geo and Street fighter layout is awkward to play on in real life and isn't worth doing. I have the same layout on my main cabinet. If you still want that layout then make the 4th button go on the right of the Streetfighter layout instead of the left (it gets in the way on the right).
Button layouts that are not curved are easier to play on, particularly when playing the fighting games that actually use all the buttons.
You do not need more than 4 buttons on the 3rd and 4th player (may not even need 4, at the moment I can't recall a single 4 player 4 button game). Gauntlet Legends could use the U360s, as can a few of the other modern 4 player games, but overall there are not many games that would need them at 3rd and 4th player positions.
That spinner is poorly placed.
Putting a playstation in there introduces a lot of complexity for very little return on your time, money and wiring investment since very few playstation games are designed for arcade controls, and as far as I know there is no easy way to interface those U360s to a playstation (I could be wrong on that, never researched it).