Wow. Springing for the APC's with your tax refund. Always interesting to see how the 1% live
A 9x4.7 and an 8x6 should pull about the same power, however be advised the 8x6 will *WANT* to fly faster and will have less thrust at low speeds. Completely your call in going for a fast 8" prop or a slow 9".
I'll still warn that's a BIG motor/battery for the FT flyer, even with the DTFB. Regardless of the prop it will fly heavy and fast, and balance will be . . . interesting.
Acro != acrobatics. In multirotors it means flying without self level assistance -- gyro assistance only -- however from the sounds of it, you're still flying with self level (no shame in that). You *can* perform some aerobatics in some auto-level modes, but still not the same as full acro.
BTW, we call it "Pilot Error," not "stupidity" . . . It sounds classier, although we all know what it means . . . mostly because we're just as guilty
As long as we learn, we're better off