From a pure technical perspective, I would guess JRuby or one of the JavaScript implementations would have been a better choice for scripting, especially given the poor state of Jython.

From a pragmatic perspective and what your users are mostly able to figure out, Python might have been the best choice. I even saw software developers with years of experience in imperative languages struggling to understand Rubys blocks...

Out of pure interest: What was the purpose of the Java application and which aspects did you allow the users of the application to script with Jython?

"Hey, how do you draw a 3d pie chart?"

"What?" I asked. "Why?"

"Well, Excel can do them. And somebody saw one. Now they want our software to draw them."

"Are you serious?"

"Yes, I need it like now. I'm supposed to demo it later today."

So I get out a sheet of paper, draw some triangles, and work out that projection math. He walks away with the paper. Half an hour later, he calls me over.

"Hey, it's a 3d pie chart!"

And there it was: On a screen I was all too familiar with, where the 2d pie chart used to be, was a squat 3d pie chart, looking like it was a fat inch thick. Of course, there was too much margin above and below, because of the flatter aspect ratio, but hey, it was 3d and it was good enough for a demo.

I think that was the first day I realized that programming can be used for evil.

It's 3d pie charts, dot charts, pie charts, and any chart that has the origin set to greater than 0 in descending order of evilness.

We need a ## anniversary edition of Lying with Statistics.