With some of ideas floating around for Gen3 with paddle shifters, roof hatches for driver extraction, production based engines, closer to road going styling cues and the like, it's almost as if there are a group of cars that feature all of this and you can buy them straight off the shelf.
Sure, they'll lose a little bit of an engineering edge with the ruleset they are based around, and they are a little power restricted (which can be taken off) but you can buy them for around the same price as what they're quoting for the Gen3 car anyway.
Surely building the new ruleset around specced up GT4 cars wouldn't do the series any harm? Besides, what other category can you buy ready to go Mustangs and Camaros straight from the factory?