Vcca regulation requirements

I managed to get something that looks workable in. It's an L-shaped island between the 1.2v and 3.3v planes that connects three of the four Vcca pins. Width is about 50 mil min, and it's parked right under the pads. I moved the more solid ground plane up a layer, so that the Vcc plane is next to last - and rerouted the clocks to avoid crossing the new plane.

The last Vcca pin is connected on the bottom of the board with a 25mil trace, which is probably overkill - since it has to neck down to 8mil to touch the pad. I may slim that track down, but I wanted to maintain a fairly decent amount of copper. All that is left is to add a couple of bypass caps to the new Vcc plane.