There are a variety of back end editors you can use with Joomla. I have found it important to jump between them for a while now. There used to be a functional "Editor Switcher" plugin (from Japan) that would allow me to change editing interfaces on the fly. Though still available it does not work for me anymore.
The "standard" way to change this is via either the Joomla - Global Configuration or the User Configuration. Those are a bit too "over-riding" for my tastes. I did do some research and I found that the JSN PowerAdmin has some shortcuts in this mode. The one they seem to document - changing on the fly - also does not show up where It seems it should. However, the PowerAdmin Menu bar, when you enable it, allows very quick changing of the assigned User Editor on the fly. I hit "Save now". Change the Editor. Close the Ariticle. Re-Open it and your alternative Editor shows itself.
You can also simply Save your article (keep it open), change your editor, then Right Click and "Relaoad" your page. Works well enough to stop complaining or look for hours for a better solution.
There are variations between editors. I am most partial to JCE Editor, but I also like ARK Editor. Additionally I have available Code Mirror Editor and TinyMCE.
I won't go chasing editors for a while. I need to do some editing.
Much of these notations are in part structured so that I myself work through the practice and reinforce my own learning. That practice is a critical piece to this or any form of technical learning. The other critical pieces are the research, the initial explorations and testing, and decision tree's going up to the practice stage of whether you want to continue down a path.
Explore and have fun. Perhaps I will enable some feedback here.