My vote goes to a 800 Monster Dark. Excellent riding position/visibility, not outrageously fast, good hooligan potential and a very under-stressed motor. A mint low-mileage one on autotrader should set you back no more than £5k, keep it garaged and the insurance could be manageable.
Or you could bet the £6k on the 3.30pm at Goodwood, and spend the winnings on 999R....
Good luck,
Ali