While I am not a mechanical guy I think I understand where you are going with this and I'd suggest it may be a difference on paper but in reality makes no noticeable difference in the performance of the AR.
you are correct.
In practice, a range from 80 degrees through 100 degrees at ride height makes little difference in real world feel.
once you go past this range, it does start to make a difference, and the further you go, the quicker it changes.
think about it this way...
the torsion bar only cares about the torque applied to it. the length of the arms doesn't matter to it.
if your arm is 10 inches long and at a 90 degree angle to the links which push up with 10 lbs of force, the forces are all at right angles and the torque transferred to the torsion bar is
(10lbf) x (10in) = 100 ft-lb
now let's say that the arm angle is 45 degrees (an extreme case, i know)
the arm pushes up with 10 lb of force, but the apparent
arm length is only 7.07 inches. This means that the sway bar feels
much stiffer than it really is.
by installing the arms at any other angle, you are shortening the effective length of the arm.
there are much more complicated dynamics that come into play with suspension travel, but this is the gist of it, and why you are encouraged to keep the arms and links at a 90 degree angle.
all this said, your installation package takes priority unless you are comfortable cutting and clearancing to make room for your arms and links.