so far the goldilocks size for me has been going just a shade wider to 205 60 15. those 65 sound a little too tall just be prepared for a little occasional rubbing on the fender. I used to go through the 195 every 7 months even with h rated tires even faster with anything rated lower than that. I don't recommend going any lower than h rated tires unless you really baby the car and dont plan on making hard on the turns.
Your best bet is LXQ1 ecu, upgraded intake the documented good ones are zxtuner top flow and roush style, iceman if you can find them, or overkill engineering, mandrel exhaust systems for catback, and the svtf exhaust manifold.