There’s no perfect replacement for the Snip tool. I want to just spr+shift+s, click/drag a box, and done. So far the closest I’ve gotten is shift+prntscrn, click/drag, enter, which is more annoying by far.
You can surely rebind that to just PRTSCR? That’s the default for me. I much prefer being able to adjust the rectangle after an initial selection, not to mention that it remembers what it last was, so that you can to multiple grabs that are perfectly positioned to evaluate or illustrate some difference.