To get nonlinear animation, would we just have to calculate that out as a formula for each frame update? For example, if we want the ball to speed up and then slow down in getting to the click destination.
What you're looking for is damping of some sort. Lerp is linear, literally stands for Linear Interpolation so it doesn't have smoothing involved. Smooth Damp can create the same effect but on a "curve". So it allows for a more gradual change in speed. Check out the documentation here: https://docs.unity3d.com/ScriptReference/Vector3.SmoothDamp.html
Ah, yea that looks like it. So many functions to remember! Thank you for your replies. I appreciate it very much.