Figured while I had it out on the bench, pulling heads would be pretty simple, and I'd have a lot better idea on the condition of the engine.
Started on cylinder 2:
Not awful, but a fair bit of carbon.
Head and gasket look ok, but dirty.
Exhaust valve
Intake valve
Cylinder 1 looks quite a bit worse:
Head:
Exhaust valve:
Intake valve:
Bores seem to look ok with no obvious damage.
Going to keep cleaning and inspecting....