Yes, sure - thanks for the reminder, I indeed wanted to react on
this. I also think that it is a very useful addition to our library.
Actually in the past it has been asked for.
Thanks for the positive response!
I don't follow the literature closely, but it seems to be an active area of research with several applications. So actually, thinking about the future, there could potentially be several concave hull strategies that have different output with regard to properties such as holes (cavities), guarantee of Jordan boundary (homeomorphic to a circle) and regularity.