I think it would be a HUGE asset to ZBrush to have a “Move Detail Brush” that would allow you to move surface details without altering the underlying topology. The current move brushes all change the topology as you push things around, which causes stretching and pinching of mesh geometry. The idea behind a “move detail brush” would be to move a shape (e.g. a surface detail) while keeping the topology intact. This would be alot like the drag dot brush which moves a shape around the existing topology without changing it’s underlying flow as the would be shape slides around the existing topology until you drop it… but instead of dragging an alpha to where you want it like the drag dot, you’ll be moving the surface details that already exist on the mesh. I suppose you could also use it to move larger things, like move a nose or an ear, letting the shape you’ve grabbed slide through the topology until you drop it at it’s new home. In other words, it’d be like a drag dot brush that first lifts the existing surface details when you start the stroke and uses that sampling as the alpha… sort of.
This has been kind of hard to explain, lol, but I see such a brush as being a HUGE asset to ZBrush, and I hope you agree and put it into the next release. 
Thanks for reading!