2000 Jeep Cherokee Back end lift

I like to know what will be the best way to raise the back end of my cherokee just a little because it seems to me that it is not level with the front end. When I have a load I seem to feel the pot holes as if I did not have any suspension more so in the back when I have people in the back seat and it dips a little more also when full. I just want to maybe level and enforce the back end. I have not updated the suspension since I brought it new though I haven't been driving it for 4 years either. I had it in storage since then. Thank You.