I have a Roush front lip which protrudes a little further that the oem lip and is supported by the front bumper, but it's no big downforce. But i'll confess..... I have a huge rear wing (pitch adjustable). Hey, I like the look, what can I say. I'll work on a more aggressive splitter next year, but even then, rules say it cannot protrude further than 2" ahead of the front bumper line.
With the rear wing and proper rake you can avoid some of the pitch sensitivity. Your aerodynamic balance will shift forward when the front pitches up and vise versa when the front pitches down. To control that you would want moderately stiff springs or 2-2.5hz ride rates and enough rebound damping to tie the car down.