Between the trackpad and the nipple, definitely the nipple.

It took so long for me to get half as good at the trackpad (after increasing its speed in the settings) as the nipple (with which I even managed to play Quake III (Old ThinkPad)). And this is saying as someone who can’t use the gamepads.

Of course mouse is best though. Never tried a vertical for long enough and fixed my carpal tunnel onset by just being more physically active.