Theoretically, it is unfortunately go big or go home game - since you already went big. If you are willing to invest time and can return the subs, I guess you could always try and eventually it might end up working better, even if against theoretical odds. 2000 series would be a better candidate though
When you say you have some pockets of heavier bass in the back of the room, is that where you have any seats and are those positions that you have included in Dirac measurements? If not that would be normal as any EQ would work only on positions you have included in the measurements. In general, the smaller the optimisation area, the better results are. So MLP plus 1 seat on left and right is easier than if you have second row of seats, or multiple seats on the side.
Also, you room is square which is not optimal, so you are facing some bass response issues that might be difficult to solve. Not expert in this area, but could explore room modes in square rooms and believe there are some models that you could use to calculate some predicted responses - and potentially how to fix them.
Finally, since you have Audy for free on your AVR, might want to fire it up as well. Would buy at least the $20 D&M app in that case as the flexibility of the built in capabilities is pretty poor. If you like what you hear, next step would be $200 Audy X app (available only on Windows though) that would give you more control over the calibration and if needed import REW filters. Audy would give you a bit more flexibility and on-the-fly adjustments, plus DEQ that is not available on Dirac. I have pretty big system and AV-10 and managing it via Audy.