First of all, the G series is a luxury sport coupe. NOT a race car. Can it be made into one? Yes. Will it be very expensive to do so? Yes.
Second, I have yet to see anyone twin turbo the AWD system on a G. I'm sure it's been done, but I'm not sure how much beefing up the trans had to go through. Putting down 450-600 hp through an automatic to 4 wheels seems like a lot to ask. Maybe it's just me.
Third, AWD cars are NEVER meant to be launched. They can be modified to take it, but realistically you're not supposed to put down ridiculous power to all 4 wheels from a stand still. It's asking for pieces to break.
Fourth, the STi or Evo would be a much better platform to make a race car out of. I'm not really sure what's going to be available in 5 years, but both cars were designed for racing. The G series was made so that you could drive past a club with an empty car and end up with 3 women as you drove away.
The Evo engine can be murdered to death and still "reliably" put down 600 awhp. The VQ engines don't take kindly to that kind of power without a lot of engine work.
As for the rear wanting to "step out" with VHS (VDC last I checked...). A 1.5 way helical LSD would help that situation improve a lot. So would wider tires and stiffer sidewalls (or larger wheels for less of a sidewall). Throw some beefier sways and coilovers and now the rear doesn't snap as easily or as unpredictable.
We've got to remember. The G series was meant to be comfortable on the freeway and in the city. Not bumpy and harsh (my evo is a touch harsh over uneven pavement).
Also, before spending 30k to make a race car (which you shouldn't be daily driving...). Go do some extensive driving in RWD and AWD cars. Having owned a modified FWD, a lightly modded high powered RWD car, and 2 high powered AWD cars, I can tell you that each has it's benefits and it's draw backs.
From the perspective of an inexperienced "racer", the FWD car will be more forgiving in turns as understeer can usually be combatted with some steering and throttle input.
The ability to make the rear "step out" on a RWD car can be used to your advantage with a little power sliding. On the flip side, oversteer is (IMO) much more difficult to combat without some good drifting background.
AWD...what to say about AWD. It handles better. But some of the characteristics of FWD and RWD that make them awesome are that in racing, two wheels can lose traction in a positive manner. In an AWD car, all 4 wheels pretty much break loose at the same time.
Granted, all of these opinions come from a mild-moderately experienced driver. I'm sure that with the proper suspension set up and the right driver, the AWD and RWD would be the only two options on the table and the majority would choose AWD.
Done with the book...back to work
