Nice list of new tools to take a look at. However I think there's just one big drawback: as you move around different systems is very unlikely that you have those (you might even not have permission to touch those systems) so you will have to rely on the standard existing tools (even among different OSes you have slightly different implementations). That's why I lately I've investing more time reading man pages of some tools, maybe I'm missing an already existing cool feature. You can learn a ton of things from man pages, and if you follow the "SEE ALSO" section you might even learn some new commands.