The exact angle, within reason, is inconsequential. The antiswaybar moves freely up and down in its holder, changing its angle (within reason) isn't going to affect how tightly the Jeep drives. All an antiswaybar does is make it harder for the left and right sides to move up and down differently from each other. It simply resists the left and right sides moving up or down differently from each other.
Quick discos won't change the feel of anything so long as your antiswaybar is somewhere in a reasonable range of acceptable angle. I've never bothered measuring any of my antiswaybar angles, "just above horizontal" is about as precise as I've ever set one.