You'll never know the flywheel condition until you get it exposed.

You'll need to get it surfaced at minimum.

As for a lighter flywheel, it all depends on your driving style. More inertial mass can get you going as well.
There is an RPM acceleration factor with lighter flywheels.

There are formulas to calculate what it would be for your application.

On my 2000 540i M Sport, I removed the hydraulic valve that slowed the clutch release. Made a big difference for shifting.