I'm working on an aggressive new design:

12 chips in 5x10cm, designed to work with a backplane.  Onboard digital Vdd control (controllable via I2C from rpi/bbb), temp monitoring (also via I2C), overtemp Vdd shutdown.  Designed to have a heatsink mounted to the back with airflow; I expect this sucker to require some cooling!  40A of Vdd current capacity allows for up to 3.3A per chip.

I'm designing the backplane system now.  The initial backplane will be a bank of four of these modules, but I have grand visions of 600GH or 1.2TH miners, with windtunnel enclosures.