What gear ratio for a street car w/occasional track use?

Stock flywheel, I would not trust that.
I would spend money on a quality SFI one before gears.
I've been using stock Flywheels for a long time, 20 yrs with a Lakewood scattershield and bellhousing never had any issue with a stock flywheel and have not had any clutch "explosions" yet either.
Everything is balanced the clutch goes with the flywheel to be neutral balanced with the rest of the rotating assembly