The perfect Auto ISO. So close, but yet so far

Imagine being able to change the auto iso "minimum shutter speed" with fn + wheel.

How powerful would Aperture priority mode become with this feature! You could keep the lens in the sweet spot and quickly change "minimum shutter speed" to ensure a sharp image and still have the lowest possible iso in different shooting conditions. I really don't understand why Nikon has not implemented this, not even in the more expensive cameras. Nikon is so close to having the perfect auto iso system, but then they make you dive into menus to change it!