There's another section further down titled "Navigation keys actions" (not to be confused with "Navigation bar tweaks").
I really hate people like me. I am thoroughly embarrassed now. jacknicholson, thanks for your patience....
A little odd topic, but what is the latest version of twrp for our beloved nexus 5?
A third party launcher like Apex or Nova should do the trick if you have to have the home or right button long-press bring it up.
Even with Sense, if you install Nova (but keep Sense as the default launcher), you can add an icon to the homescre...
Is the one I use. There are other options.