Thank you all so much for your help yesterday. I've made a number of design adjustments, and it definitely looks more manageable (at least to me).
I'm hoping to get approx 1 Watt at 8 Ohms out, using a 12v supply. The design is based off of a number of other amps, including the Leak 30, El Cheapo, Z30/50, etc. As I made a few adjustments yesterday, I also realized the topology is becoming closer to a 60s Fender Princeton, though using BJTs.
Stage 1: peaking current/gm-compensated Stage 2: buffer (emitter follower) Stage 3: quasi-complementary output, driven by a unity gain phase splitter
No. It's not. You're using a unique topology that was originally used to eliminate the output transformer in shirt pocket radios.
A quasi-complementary is just like a complementary amplifier except the bottom darlington has been replaced with a Sziklai pair. It's prone to oscillation and was only used because older PNP power transistors were exceptionally poor performers.
Come again? That output stage you have can only be operated as class AB or class A. It's (almost) always used class AB.
Don't be a Richard. You can use all the help you can get with this and there's people here that can help you. So don't be some armchair engineer when you don't even know basic terminology and act like a complete phallus and expect people to want to help you.