I think there's a lot of room to give the Z35 a more than merely cosmetic refresh while making use of the existing Q60 platform.
They could match it to a direct injection head, offer a boosted option, refine the two trans options further, etc.
The real key, I think, will be whether or not they can shed some weight and add some extra N/A power. If they can drop the next Z by, say, 100 lbs, and bump the output up by 25 lbft of torque and and add 30+ bhp, the weight loss plus extra pull will make it feel like a totally different car out of the box.
Just wondering, but how different is the Q60 from the G37 in weight, handling, etc?
EDIT: Wait, I just looked it up... so other than the IPL version (essentially a Nismo Q60) the differences are just cosmetic???
C&D even reported the same right hander fuel starve -- 'da ****?