It is not so much the curve of the springs, but the number of leafs combined with the curve that gives you your lift. You start pullin leafs, you'll start losin inches. Unfurtunately, when you lift a leaf sprung vehicle, the comfort definately suffers. Also remember that you have removed the rear anti-sway bar. I have a 98 with a RE 3.5" and 31x10.50's. It is my DD. I can get into some pretty gnarly traffic too, traveling at highway speeds. To make up for the removal of the sway bar and the higher center of gravity, (I tow a trailer often too.) I've stiffened my rear end even further. I've added a set of helper springs and run wheels with 3 1/2" of back spacing. Yeah the rear end is stiff. You don't want to be in the back seat when goin over a parking lot speed bump. But it feel just as, if not more stable then it did before the lift.
But it is a Jeep. I don't think you will ever get it to ride like a Cadi, atleast not without substantial rollover risk. It only takes a little jerk of the wheel at highway speeds (with a soft spring pack and no rear sway bar), the rear of the vehicle leans too far over and well ..........I don't know of any Jeep that rides smoothly on it's roof......then wheels, then roof, then wheels ....... Not to mention that you will look lilke a fool havin to pick all of your gear up out of the road that came flyin out of what used to be your Jeep.
To soften up some of the bigger bumps, just lift your back off the seat. Just an inch or two will do. Try installing a suspended type seat.
