PCB: Lessons learned

Excuse the long delay, this PCB took forever to arrive.

The PCBs arrived today, and I've already learned a few lessons.

1. Make solder pads as big as possible. 
2. Ensure pinholes are large enough to accept square pins of the same size
3. Leave room for error corrections
4. Create test point vias

In addition to those minor annoyances, I made a mistake in the schematic. The trim resistor is supposed to be connected to ground!