I quite frequently add a file hunk by hunk to the staging area. With GitX for example the button to "stage" will always be at the top right and when I click it the button for the next hunk will move there.

In Sourcetree however the buttons are at the bottom of the hunk so after every click of "Stage Hunk" I have to scroll around to find the next one. It would be much more convenient to have the buttons at the top of each hunk.