I know you don't want to hear it, and you probably take pride in being different and taking the road less travelled, but as someone who had a 1G NT and did a couple mods to it then got a 1G AWD, and then another 1G AWD. You really want to go to a factory turbo AWD car.
The difference is ridiculous. I couldn't believe how different the cars were. You keep the looks and the familiarity with the car you love but the AWD suspension makes for way better handling, feels so much more planted. The power is ridiculous in comparison. The NTs actually have good bottom end grunt compared to other NT 4 bangers in it's class but to add the turbo is a world of difference.
Even the other little stuff, the TSi seats are more supportive and form fitting, the leather wrap steering wheel is nicer in the hands. Of course out here too the traction of AWD is so awesome. The first time I did a 4000rpm full out launch on wet pavement in the rain and pinned myself back in the seat I was totally hooked. The NT or FWD Turbo for that matter just sit and spin, but to have that kind of thrust available in almost any weather is epic.
Damn... I gotta put my car back together...
Oh, another thing too is the modding. In my NT I never spent big bucks but I spent a bunch of time fabbing up some cool ram air airbox and intake and when I was done I thought I could tell a difference. It was the first car I really modded and I started to think that's what modding was like, you'd spend a bunch of time and money and think you could tell a little difference. But to compare to the turbos, I swapped a 14b for an Evo3 16g, went from 14psi on the 14b to about 9 psi on the 16g to make sure it was running good and I thought it'd be a wash but it was obvious, even to passengers, how much power it picked up. That was before even turning the boost up which again made a big difference. Mods are so much more rewarding on the turbo cars.