My opinion,
Without isolators, you have metal-on-metal contact, and NVH (noise, vibration, harshness) will increase and this will affect your ride quality. I've read about people using an inner tube, electrical tape to help lower the NVH but honestly, do it the right way, and buy the right part for the job. I'm sure if you check CJ Pony Parts, LMR, or MM they sell spring isolators for your vehicle.
If you're looking for a certain ride height do it the correct way, get coil-overs where your ride height is adjustable or purchase an air ride suspension. And for the budget-minded, purchase a spring that gives you something close to the ride height you're looking for and use new spring isolators.
Good luck
Michael Plummer