Maybe my area is different, but $1 per play is going to turn off a lot of people. I personally wouldn't frequent a place charging $1 a game and I only play on location. On new titles sure, but for pretty much anything else $0.75 a game will probably bring in more volume. Heck at a truck stop I like to go to, the most popular game is Metallica simply because it is set to $0.50 a play. I think your prices are on the low end of what I see out on location, with the level of maintenance you are talking about it is unheard of.
I think $0.75 per game on everything, but keep one priced at $0.50 to keep the cheapskates playing. You might be able to get away with $1 per game on a new game if there are a lot of more knowledgeable pinball players who come in. Otherwise, the only thing that will make Ghostbusters stand out to a new player is the higher price tag. JJP's games could probably get away with being $1 when new, but even then most of the ones I see on location drop down to $0.75 pretty quick.