What a beautiful room! My wife and I used to own a big 1903 home with rooms like that. I loved that house, but the upkeep was killing us. Had to let it go.
The reason your drums sounded so great there was because of the entryway directly behind you. Apparently it was just the right size that the sound waves emanating from behind your kit were aligning perfectly as they exited the room with the direct sound waves so that it acted as a sonic reenforcement and a perfect reverb effect. The crappy sound from the PA was happenstance as well. Square room, tall ceilings, practically no room treatment all adds up to standing waves galore. And those JBL Eon speakers (I presume) you were using as monitors were adding to the cacaphony by creating time delay with the main speakers. Add that to the aforementioned problems and . . . . well, you get what you had. Lucky you. At least if you need to record your drums some time in the future, you'll know exactly where to go!
Nice looking drumset, by the way.
GeeDeeEmm