Ahh, yes, great point about the need to bi-amp here to really get the full active loudspeaker effect. No problem, though, as that's easily accomplished with the minidsp SHD.
You can drop in the filers specified in that link (the ones for the biamp setu) and then use the dual outputs from the minidsp into whatever 4 channels of amplifications you want.
Yep, the minidsp can still run Dirac (room correction) after the EQ filters have been applied. Plus, its ADC is supposed to be very good should one want to run vinyl.