Wow, impressive collection - thank you for sharing.
I'm not into collecting arcade PCB's, although I may start in the future. What puts me off is how temperamental these things are. They work perfectly one day, then you store them & pull them out only to find that they no longer work. Batteries leak, Capcom's suicide, chips die, boards sag, it just seems futile.
That said, I do have a couple of boards.
I absolutely loved playing Neo Geo arcade games as a kid so this one was a must have for me.
Neo Geo MV-1F:
I remember playing this at a fish & chip shop after school. They also had Double Dragon & Cabal in there too. I bought it off eBay as non-working for $1. It is extremely clean, a friend of mine fixed it in about 2 minutes. Just needed a RAM chip replaced and a broken solder mended.
Shadow Warriors (aka Ninja Gaiden):