8x10 is a small room. Your room is almost triple that and should be able to easily accommodate a mid-sized floorstander such as the Monitor Audio Silver RX6, the PSB Synchrony Two T, Magnepan 1.7 plus a small sub, Mirage OMD-15, Totem Hawk or Sttaf.
I think a particularly good candidate would be the GoldenEar Triton Three Tower. It is a fairly compact tower with a built-in powered (sub)woofer. This would make it easier to adjust the bass output to a range of room sizes, and your room size would be in its sweet spot. It also have a very fast, linear midrange and very smooth, resolving, extended folded ribbon tweeter based on the Heil design.
Although they're pretty accessible and affordable, these are highly resolving speakers that will make full use of your Pass Labs electronics.
I think a particularly good candidate would be the GoldenEar Triton Three Tower. It is a fairly compact tower with a built-in powered (sub)woofer. This would make it easier to adjust the bass output to a range of room sizes, and your room size would be in its sweet spot. It also have a very fast, linear midrange and very smooth, resolving, extended folded ribbon tweeter based on the Heil design.
Although they're pretty accessible and affordable, these are highly resolving speakers that will make full use of your Pass Labs electronics.