It is very subjective: For me the smaller the better, if you give a track point instead. I do not understand why people want to move there hand so much while working...
Honestly most of the reason I like a big touchpad is gestures. On mac especially. Switching desktops is 3 fingers to the side. My fingers aren't that small, it's a lot easier to do it on a big trackpad. I never really practiced with a track point when I had one, so I was maddeningly imprecise. Having a big touch pad lets me have more room for error on cursor movement. To do that I have to move my hand slightly more to get to the center of the pad. As you said it's subjective.
