Well the highest power draw is definitely going to come from 2 of these motors http://banebots.com/p/M5-RS550-12 which list 14.4V/85A max power draw. Obviously I wouldn't want to run them at that for any length of time, but is there a way to narrow my search for boards that will handle that voltage, the moderate needs of a few smaller motors/servos, and the modest needs of a microcontroller and a few sensors. It is a team of robots with slightly different configurations, but the motors and controllers are the same, and I'd like to use the same board across each for consistency.
Well just as a general statement one wouldn't normally want or need to supply regulated DC voltage to motors running at 14.4V/85A, but rather just power them directly from lead acid or Li-Po battery packs via a suitably rated motor controller. Then all the other electronics requiring regulated DC would be powered via switching regulator modules that would also use the raw 14.4vdc as their input voltage.
Yes that would make a lot more sense wouldn't it... I don't suppose there is a board that already combines a voltage regulator for the control circuit and the speed controller/relays for the brushed motors in one is there?