Piston shape is going to vary depending on make/model/motor. The piston design itself shouldn't be messed with. Nissan spent 100's of thousands of dollars designing the KA, to include the combustion chamber. Unless you're an engineer, don't over think something like quench and or the very slight difference in compression between motors. IMHO, that would be a complete waste. Something as simple as ring placement can change your whole compression profile.
Quench is basically how the motor avoids detonation. Mess with the quench zone and you're just going to have trouble. Flat top pistons will lead to smashed valves
I've rebuilt plenty of motors without using a torque plate. If you're making the kind of power that requires a torque plate, you're not worried about a budget. If you're not worried about a budget then you're using aftermarket everything, so you won't need to worry about having something turned or refurbed in any way.
WD