Nah... Ferrari make V8's that rev to 8500rpm so what's the big issue with another 1000rpm? Non-issue IMO.
Put a 7 speed gearbox in, widen the ratio's slightly, BAM!!! You might reduce wheelspin a bit! Maybe you could widen the rear tyres a bit but the tyre width is kinda wide for RL cars...
He's never drive a car before so he doesn't yet realise that when you want to go fast, a fiddly stereo just gets in the way! Standard stereos do exactly what's needed; higher level stuff adds more speakers/woofers and allows for more fine-tuning, that's it.
Raise the car or stiffen the springs until there is no bottoming out. This is an easy fix and the original problem could have been caused by a export glitch!
Understeer keeps the driver alive! As per my prior comment, this reveals abg7's lack of driving knowledge. Push too hard you get understeer, drive on the street you WANT understeer! A car that oversteers all the time is a death-trap!
This is purely subjective but has a basis in truth. A Ferrari 488 Italia isn't a supercar; it's a top shelf sports car. It's insanely fast but it lacks the nebulous last degree of exclusivity that defines a super or hypercar from their lesser brethren. Think Gallardo vs. Murcielago...
IMO, your car is fine apart from perhaps some suspension fine-tuning and I wouldn't worry so much!