Stuka

A body lift gives no ground clearance, so i wouldnt even consider that. All it does is raise your center of gravity and put more stress on body mounts. Since you have a coil lift, you can put spacers in front and back with no issues. Other than if you don't have adjustable control arms or track bars, you are going to want them with the extra lift.

Calypso

That's not a very smart statement. No, a bl dosn't give you more ground clearence but neither will spacers. The only way to get ground clearence is with BIGGER TIRES. Coils, spacers or bl's do not raise the axles. As far as the center of gravity, the above statement is really off as a bl raises your COG less that a suspension lift because only the weight of the body is raised.

Do what you want to your JK as you can put spacers on top of your coil suspension. Just know that you may have to change your DS and possibly get control arms to get it to drive better. With a bl, you would need to do nothing else.

Stuka

To gain on clearance under the axles yes. But a suspension lift does give you a better aproach angle, departure angle, and break over angle. Clearance under the axles is one of the less important clearances, as in most cases a decent driver and keep the tires on the high spots. But getter high centered is much more common, and hard to prevent.

And yes a suspension lift does raise the center of gravity as well, but you gain the above mentioned ground clearances in return. A body lift wont give you any of these gains.