To be fair, a new car isn't a stupid idea. £6k + the sale price of your 182 gives you a lot of choice.
If you have your heart set on spending some money on it though, I'd personally do the below -
Ensure you have some decent tyres. I really rate the Pirelli P-Zeros, but looking to try AD08's next.
Refresh the suspension components (new dampers/shocks, springs, track rods, ball joints, bushes, etc.).
Upgrade the front brakes to Brembo HC discs and DS2500's pads (even OEM pads are sufficient for road use though). Braided lines are worth getting also. Leave the rears as they are/replace for standard if required.
A yanoo stiff shift kit, Powerflex dogbone mount and fluid change should see a nice improvement to the gear change.
Recaro Trendlines (from a Trophy/R26 etc.), really good seats- supportive yet retain practicality. New steering wheel to replace the bus-like standard one.
Just a few ideas for you. There's an endless amount of things you can do with these cars.....