Personally, I'm a bit in the same thought...
I bought an AT to keep myself "out of trouble" and from going "mod happy". However...lol...that's not really stopped me, I've just hit the limit and still want more, and I still get myself into trouble - but truth be told, I'd have more control without it being an AT - because I can always stomp on the clutch for instant power removal, instead of relying on the engine to spin down hard enough, or the torque converter to release when it wants to.
I also compromised on the color (I wanted plat)...so, for me, is it worth trading in a perfectly good 7AT black touring/sport with all the options except nac, a FI cat-back, and a G3 intake, for a new PG 6MT touring/sport bone-stock...AND...have to pay 4-6K in depreciation, even though I have a total of 3750 miles on the Z? No.
That said, I have considered trading it on a Mustang with a 5.0 (which I'd promptly dump more money into) or even a top-level Camaro SS (which in person doesn't look bad...just some camera angles it's like waking up the next morning after boozing and realizing what you brought home...), and also putting in a roots SC...
Anyhow...