I gotcha, and I dont want to get into “legit street car” mumbojumbo in your thread.
My thoughts were some I am sure you may have already thought about. The light wheels and tires will make a decent change for the better to start.
Your car is to the point that its the little things that make the differences now. What about lighter brake rotors? chromo axles? Chromo suspension arms? CF hood and trunk?
Many will argue the weight vs power stuff till the sun comes up. Is it worth the time and money to shed 100lbs? or invest it into 20hp?