Wheelbase is a huge consideration when moving to a long trailer and short wheelbase vehicle as discussed above. You don't want the tail wagging the dog. I too had a grand cherokee "rated" to tow ~6000. Even w/ the springs/hitch set up for this weight it was much too squirrelly in my opinion. Having had the wind catch a trailer on the back of a pickup truck in my earlier years makes me a bit more cautious however. I don't want any "seat feel" when pulling a trailer.
