Although all panes are resizable, none of the positions are remembered in between sessions, which makes the resizing feature almost pointless. The defaults are probably ok for some people, but I usually prefer a much wider diff view and higher commit history view as that fits my workflow (see first attachment).
However after every restart the layout simply reverts to what it was before (see second attachment). This should be saved and restored - not just the ones in the screenshots, but all of them. (IIRC this was the case in 1.5.x?)