Pack GUI widgets tighter on Mac
On Mac, all the GUI components have wide spacing (such as in the toolbars and the inspectors). Although this wide spacing is typical of Mac applications, ParaView has many more options than a typical application. All these GUI components are encroaching on the views and tend to make you have to scroll more through options. I thus advocate packing all the widgets tighter. Although it will look a bit less friendly, it will be more functional.
David Partyka commented
I've enountered errors with test playback because of this due to the fact that some of the toolbar buttons get collapsed. If anyone knows how to control the packing let me know. I wouldn't mind experimenting with it.