Ha...Did not take you long to get the bug James...I think if I still owned it I would be thinking about the Litchfield susp kit and uprated ARB;s. Maybe some brake cooling as well if you found them getting a bit long on a trackday.
By the way it already has Castrol SRF brake fluid and goodridge hoses as supplied by Ian Litchfield.
Maybe do your driver training with CAT, get a a trackday and see how you feel about the car, does it lack power/brakes/handling or is anything overheating?? Then plan from that starting point.
By the way on track those R888's will trounce them Michelins on a dry track. Pure physics of the amount of rubber in contact with the track wins it every time.