Unfortunately NI isn't great for insurance! However your quotes do seem a bit excessive.
I'm 23 with 3yrs no claims and insured on my 06 GTI with directline for about £1300. I'm going to renew with Greenlight next month. A previous quote from them was in the region of £1100 for me. So I would imagine would be considerably less for you, given your age and experience.
My younger brother got a great quote through HIC for a modified 2.0TDI passat - with wheels, coilovers, stereo, xenons and everything else declared. They may be worth a try also.