Ah, grasshopper.... You have come to the right place!
For a daily-driver, I would stay away from anything labeled "track," "competition," "race," or any other synonym of that ilk. You won't be happy with the results... There's essentially two schools of thought for the suspension design, either heavy springs and light swaybars, or light springs and heavy swaybars. The first will corner flat, have little brake dive, and ride like a truck; the second will corner flat, have some brake dive, but not knock the fillings out of your molars on a pothole. The stuff designed for the street anticipates the usual gamut of road conditions, like potholes, speed bumps, railroad crossings, etc, and is set up to allow for enough compliance to keep the tires planted under those conditions. The competition/track stuff is geared more towards the open track, which is ruler flat in comparison to the average street.
Now to the heart of the matter... If your main complaint is that you're sliding around in the seat, it's not body roll that's the culprit, it's centrifigul force. Whether you're getting 15* of roll in the body or 3* of roll, your butt will want to move towards the door in a hurry on a hard right-hander, and here is the only solution:
It's only a half-joke. I wouldn't put a competition seat into a daily-driver, but you may want to look at upgrading your seat to something with some serious side bolsters, like Sparco, Cobra, or Bride's street pieces. Still plenty cushy for the long rides, but with real lateral support to help keep you planted. Before I put the Ultrashield seats in mine, every time I went to the track I had two huge bruises on my legs: Left outer calf (bracing against the speaker grille) and right outer knee (center stack) and my forearms were exhausted from bracing against the wheel. After the seat install, I drive with my fingertips, and my legs are unbruised. QED.