You have 17 in. rims? This is probably what is causing a lot of the harshness. If you can't change this, either go to a bigger tire size or live with the roughness.
You should probably get new shocks. If you can't afford Old Man Emu shocks, Monroe makes a gas shock that can be adjusted. They provide a fairly smooth ride that can be customized to your Jeep. Also, you can buy new coils that have a different spring rate, which will change your ride as well.
But, like I said, if you continue to stick with your 17 in. rims and a tire that is smaller than a 33, you will probably just have to suffer a bit.