That scene would also be a good place to start. The reason I like the Casino planet first, however, is that it would allow a great deal of specificity about Finn and Rose which would be necessary to understanding what’s going on.
On another note, something that bugs me:
“And this is the lesson. That Force does not belong to the Jedi.
To say that if the Jedi die the light dies is vanity, can you feel that?
There’s something else…”
I’d remove the sentence about vanity, since his meaning is clear with his first two sentences. This scene is one of my favorites in the movie, and this line is one of many in the movie that overexplain and end up being a detriment to the tone.