I would like to see, and even if they are $ options that would be fine, though I know some of this is pipe dreams-
Real leather steering wheel with thick bolstered/padded areas.
Different interior colors other then black.
Interior leather/upscale upgrade like the corvette 4LT option.
Real brakes-If you can afford to put Brembo's on the Cobalt SS you can do it for the camaro.
and the CTS-V as well!!
The exact wheels on the orange convertible show car.
Room to fit at least 9.5 wide up front and 11 wide out back wheel.

...
we going to need them!
Some higher end strut/shocks- Would like to see Koni, Bilstein, etc. For that matter a magnetic system.
A front grill made out of metal.
Too much weight...but there might be one that looks metal
Open up the hood scoop.
Some kind of CME (center mount exhaust).