Wow, this is an old thread. But, I'm glad I found it rather than creating a new one.
I'm thinking the same thing now, but only about the Trackball. The spinner is a must for me for the likes of Arkanoid, Tempest, Discs Of Tron (push/pull), Super Sprint ...and Off Road, I'll assume, etc.
The trackball is where I'm flip flopping.

If I didn't have one, would I absolutely miss Centipede, Millipede, Missile Command and Marble Madness? Yeah, but not
terribly. These games always frustrated the hell out of me. It was always a couple levels and done. Not like Asteroids, Donkey Kong, Joust, Q*Bert, Ms. Pac-Man, Berzerk, Elevator Action, and the like.

Would my guests, my kids, guests' kids and women (Centipede) miss those games? What about Bowling and Golf games, which I'm not into? Should I worry about that stuff? For bowling, the kids can go play the wii! Plus, they'll have hundreds of other games to choose from!
What I would miss is Reactor, but I only remembered it when researching 'trackball or no trackball'. I'd also like to try Shuffleshot, but haven't yet. Same with American Horseshoes. They look like very cool games. But... I'm planning on adding a real shuffleboard table to my basement, so a little less of a need.
In the end, do I save the space by omitting the trackball and try to make a control panel that can fit into my original size Space Duel cab?
Or will I regret it because of the games and the ability to use the trackball as a mouse?
I know this is personal preference, but a multitude of opinions sure can help. I really hadn't thought of losing the mouse/navigation feature until reading here! That's at least one thing to ponder...