Why can't they offer stock Ubuntu + the monitoring stuff as a .deb? They can put up lots of instructions about how to enable panel integration. They could run their own apt repository too, which should satisfy anyone who wants to spin up instances via API and configure via some CM tool. Seems like this would satisfy all needs.

I second this. Also it means you don't have to examine the distribution after setting up a new box to find all the little things they have modified.