Lamé / Squircle rounded corners
It would be great to add a way to create Lamé curved corners with rounded corners. (See the section "Optical corner rounding" in https://medium.muz.li/optical-effects-9fca82b4cd9a for an example of this.) Right now, one can make geometric round corners in Adobe Illustrator (and InDesign), but it would add greater flexibility to designs to use Lamé curves to create these more nuanced curves.
Jordan Biffle commented
I'd like for the corner tool to have more options for rounding corners for "squircle" shapes that feature a slower radius at the start, and ramp up to a faster radius at the corner. The best example I can give of this are the icons used in iOS, but it would be really helpful for artists to prevent the "sagging" illusion that single radiuses can sometimes give.
Meanwhile AstuteGraphics offer a DynamicCorners plugin that has a 'squircular' corner method, a good approximation, suitable for practical cases, that uses longer handles, as the linked articles suggests as a workaround.
Zed Man commented
in the meantime, we can use the shape of Lamé curves as masking for rounded corners