While I was able to make the r2 power distribution board work, it did require quite a bit more than my usual number of blue wires and careful trace cutting.
Thus I spun a new revision r3, basically just to fix all the blue wires so that I could have some spares without having to worry about the robustness of my hot glue. While I was at it, I updated the logo:
As seems to be the way of things, a few days after I sent this board off to be manufactured, I realized that the CAN port needed to actually be isolated, since when the switches are off, the ground is disconnected from the rest of the system. Sigh. Guess that will wait for r4.
Here is r3 all wired up into the chassis: