In addition to that the Hardware should also be opensourced, like how to build the most optimal gaming console to work on Steam OS...
But It will all come down to the gaming pad, how the gaming pad will be designed and how it will integrate with build your own systems
Steam is a DRM platform with a few user features on top. Releasing an open source platform would be as uncharacteristic as suicidal.
In addition to that the Hardware should also be opensourced, like how to build the most optimal gaming console to work on Steam OS...
But It will all come down to the gaming pad, how the gaming pad will be designed and how it will integrate with build your own systems