What if you just change the 0.5 factor based on some function of distance, like maybe the square or 1.5th power, or a hand-tweaked polynomial curve? I suspect

What if you just change the 0.5 factor based on some function of distance, like maybe the square or 1.5th power, or a hand-tweaked polynomial curve? I suspect something based on real physics would look subtly more natural, but not having a math education I suspect I'd probably try that first, maybe with the addition of some nonsense non-physically-inspired inertia modifier.