To be honest, since this is your first game, I wouldn't do anything. Play it a little while, see how you like it, then figure out what you might want to do to enhance it. Gb seems to have airball and slimer issues, both of which affect game play, so maybe focus on that. We have lighting mods for GB and a cool ecto car, but I wouldn't start there with your first pin.

Dimples are normal, don't lose any sleep over them. Stern rubber is perfectly fine, maybe change out the balls to the polished ones pinball life sells. Old pings on here I believe has an airball deflector.

Our mods are at Lermods.com.

Enjoy the game, it's a great first pin.

Not a "keychain" car...

http://lermods.com/products/ghostbusters-pinball-illuminated-flashing-sirens-ecto-1-car-mod

Think about what costs there are running a business and time isn't free. Most of our mods are pretty competitively priced, but there are some that just cost more, this is one of our highest priced mods, but it takes time to make it. We also pretty much guaranteed our mods for life...yes, for life! Have an issue with one of our mods, send it back and we'll fix it free or replace it. That should be worth something for a buyer. This is a really cool mod!