To keep the board simple and allow for user upgrade/modification in regards to IMUs and multi-axis sensors (9 axis), we are temporarily considering using the GY-85 board. Even though the compass chip is no longer being manufactured, this board is currently still available.
https://github.com/madc/GY-85However, given the Proto is a 1DOF simulator, the digital compass may be able to provide angular rates, as in degrees per second.