I have a dedicated Pause, and it gets used a ton. In fact, it's almost my generic "command button", because with various shifts I also use it to access the config menu, save state, and load state. It's mapped to P, so it also pauses in many PC games.
The only other "command" buttons on my CP are Exit and a dedicated Shift button. (The Shift button changes game lists in the front end.) Coins are handled through the coin door, either by inserting a coin or pressing in the coin return buttons.
--Chris