ted... here are a few things that would/could improve your car....
(sugestions)
de badged front grill ( 20 quid max)
aero flat blade wipers for the front (about a tenner)
grommet for back wiper and get rid of wiper arm and motor.
take the badges off door and boot
you could spray your boot lock arden blue? using rattle cans from halfords
smoked side indicators/ repeaters
interior:
chrome gaiter surround and remove that horrible plastic surround
white dial kit and chrome surrounds
blue leater gaitor and handbrake cover
simple things like this
you could ask your insurence about a gsi/sport spoiler because it only looks nice dosent effect performence etc. quindirect dont care bout asthetics aslong as u declair