Created attachment 352057 [details]
illustration showing header bar use with extra title information, e.g. last invoked command line

see illustration - to make better use of the Gnome Shell header bar UI style, split the window title over 2 lines, and use the extra space to show additional information, for example the most recently issued command.  

Choose exact split of these pieces of information (username@hostname, location, last invoked command line) between 2 lines optimally.