Maurice Valimberti passed on this May 20th Jupiter image for posting on the forum. The amount of detail he gets is astonishing. He uses a 14" SCT, a 740k ToU Cam that is "tricked up" (dont ask me for exact details) and uses IRIS for processing.
In talking with him, the astonishing thing about this image is that shows Io being partly eclipsed by Jupiter's shadow, and you can see the phase on Io. I think that there was a window of only a few minutes for this to be visible.
You could also align on Io separately and only include the frames where it stayed still and showed the phase. That way you could still capture for the full 2 minutes to get enough frames for Jupiter, and only use the frames you want for Io.