If you really want to stick to Europe, here are some things to think about:
There are not that many places worth-wile in Europe. You can divide them in three sections:
1) The modern-day still around arcades. I know they are still there in Scheveningen, Renesse, Vlissingen, a brand new one in Tilburg, not sure if the place with the 360 near Venlo is still open ?, some arcades in Valkenburg might still be there.
However, don't expect a lot of classics or even candies. The Belgian coast-line was always famous for arcades, just like the British with it's piers, but they all have the same problem....less and less videogames, more and more redemption games.
2) Museums/Clubs. Those are interesting but pretty rare. There's a very nice museum in Denmark:
http://www.playright.dk/museum/udstilling/I also know of a club in Karlsruhe
http://www.retrogames.info which looks very cool. AFAIK these are both not open everyday, so you will have to carefully plan your visits.
The Berlin museum is ...uh.....hotly debated here.....
https://www.dragonslairfans.com/smfor/index.php?topic=2458.03) Private collectors. Of course, with these guys, it all depends if they are willing and able to receive you. Some of these people throw yearly parties, so they can "focus" all those visitors on one date. But again, some guys may PM you if you are welcome

You're welcome in my gameroom, but I have the same problem....I'll need to clear it up for you guys to visit and "be around" the day you would visit...this is one (small) reason to organize Eurocades
