I do a ton of micro edits (stretching or shrinking captions, images and video clips to sync with updated versions of soundtracks). When I want to move a clip I have the snap-to to help me.
I would love to have something similar when stretching or shrinking. My suggestion is that, when the clip is selected I can press ctrl + left or right arrow (or something similar) and have the start or end of the clip stretch or shrink to the playhead. Obviously would not be activated for the start of the clip if the masthead was after the end of the clip (or for the end of the clip if the masthead was before the start).
Tbh, it would also help to be able to move the clip to start or finish at the playhead as well, but the need is not as urgent as for stretching/shrinking.