Yeah leave aero alone for a while, would agree. This car does not need a ton of aero in the rear to put in good times. If the problem is the springs, don't fix the springs by adding more aero.
Like 350 said, it takes a long time to dial in. My car was barely drivable, scared the hell out of me from last august to just this april. It's not gran turismo unfortunately lol, it takes a long long time. If you keep adding problems on top of problems, you will never figure anything out.