It would be awesome if it was possible to change the way that the commit details and diff are organized in the SourceTree window.

 

Right now the details view is split between commit message, files and so on (on the left side) and diff (on the right). But it would be more convenient for some people to have a wider diff area taking up the whole width. I think the main details and diff could be stacked horizontally or maybe the details view could be merged with the history view. If these panels could be dragged and dropped dynamically like in some IDEs that would make it very flexible.