The wiki suggests either MPlot or WxMpl for embedding. Which might be preferable for a display-only use? In other words, what would be the simpliest, easiest, most pragmatic approach?

So far in my experience, and as I was recommended, the "simpliest, easiest,
most pragmatic approach" has been to forgo MPlot or WxMpl and just embed
directly in wxPython. 

This page discusses the difference between direct embedding and using
an embedding library, the key difference for you being this sentence: 
"An embedding library saves you a lot of time and effort by providing
plotting widgets that already support user interactions and other bells and
whistles."  But you don't want such bells and whistles.  There is a link on
that page to this example of direct embedding with wx.  I was able to start
with this and adapt it to my needs.