I still have my copy of Skitch installed, and agree, it is and was the best solution for so many use cases.

However, given the fact that it has been abandonware for a long time now, I did look for alternatives for that fateful day when Apple fucks up macOS sufficiently where Skitch is no longer executable, which is not a question of if, but a matter of when.

I decided that CleanShot X was the closest thing to a suitable alternative to Skitch, although it has a number of really annoying design decisions that keep it from being a suitable replacement for Skitch, unfortunately.

If someone could convince the owners of the Skitch IP to open source it, I would be very interested in helping maintain it.