You could reassign the keys needed for Exposé and Spaces, no? I have a early 2008 MacBook so all F-keys except F5 and F6 are occupied by various system control buttons (play/pause, dashboard etc).
One of the things that bugs me about OS X is that the volume adjustments made via the keyboard-based volume keys move in steps that are too large. Invariably, I’ll move the volume down a notch, and it ...