I got some email from Dave at Priority. He had some feedback about what I've written here.

The headset is normally notchy from the factory, he says it will smooth out after about a hundred miles, same with the front hub. The packaging for the fork ends and the wrench design are being changed for the next production run. There's not yet any lower gearing option... they have the medium front and largest rear pulley, and putting on the smallest front would make the drivetrain too long for the dropouts. The hub clicking is normal (confirmed with research elsewhere). The roller is there to keep the belt from skipping at that point under heavy torque. I'm going edit my posts a little, I don't want people to think that what I've posted is what they'll get if Priority is going to change it.

Unasked for, he is sending me the front brake kit. I didn't pay for this bike in the first place so I definitely wasn't looking for any kind of comp for the little problems. But he says with a baby on board or in tow they'd prefer a rider have the extra stopping power. I'm sort of conflicted about this, if I have a front brake I'm probably not going to use the coaster much at all.