So it seems like there's not a lot of activity with this kernel in terms of people playing with voltages and stuff like that.
Since I'm at home bored today waiting for a flight, I figured I'd play around.
So far I've bumped each speed's voltage down two steps (so 70 60 46 31) and it seems stable. Two below that, webosmark triggers a reboot.
All radios on, brightness at 50%, seeing between -134 and -185 mA battery current sitting fairly idle at 300MHz. When the screen dims to min brightness when inactive, it dips to -90 to -110 mA.
I only have about an hour at these voltages, I think I'll just stay here for the day and try to get some data in terms of battery drain per hour.