Agreed, the new Jeep GRAND cherokee is not a good offroad rig.
The unibody Jeep CHEROKEE XJ with F&R solid axles is a great platform to build for offroading. Bet you didn't know it was a unibody
Back to your comment, I use rear solid axle (other than the H1) & 4 low transfer case as a minimum benchmark for offroading platforms rather than frame design. The Cherokee proves that unibodies can be used on more than just cars.