[kenferry]

> Get rid of that silly big screen on Apple watch. Put the touch sensor there. Why not just allow thumbprint scan, wave my watch at a Apple Pay terminal, and buy things? Way less effort than taking out my phone.

Just in case you missed it, this is already supported, and it's somewhat better than you're suggesting. Once the watch is unlocked, it does not need additional authentication to pay until it leaves your wrist (at which point it relocks). Double click the side button to put it into pay mode.