Cutting the springs will make them stiffer, and there is probably a formula (any engineers out there?) you can use to determine how much stiffer, depending on how much you shorten them. Aftermarket springs are (theoretically) designed to provide a proportional increase in spring rates front and rear.
I do not know the spring rates for stock, variable rate Eibach, factory ACR springs, or other aftermarket coil overs. I would probably look for a single rate aftermarket coil over system with adjustable shocks. You can then lower the car as as much as you want and set the corner weights. My experience has been that more then an inch or so lower on a street car reduces the ride/handling compromise to a point where it is unsatisfactory.
Also, you will probably need stiffer shocks if you go with stiffer springs. The factory shocks may not be stiff enough to control the increased rates of aftermarket springs.
Jim