Freeze-framing the shot doesn't seem to indicate that his Lightsaber handle was affected during this. If the sparks stay, would it be possible to have a small part of the bottom of Luke's Lightsaber handle being chopped off at the same time as the hand, and have the small piece falling away too, to explain the 'sparking'?
On the exterior model shot 'close-up' of the Medical Frigate ship near the end, as we pan left towards the inset 'window area' portal' (which it would still be great to see a small R2 and C3PO staring out of....), it seems that the actual angles of this 'inset', lit-up portion don't match the full size set ones. Could you amend them to do so?
Going back to perhaps adding a red 'light' dot to the end 'close-ups' of the Millennium Falcon model at the end- It might look really good to also add the two red 'lights' to the front ends to, to also match the look of the Falcon as seen on the platform of the 'floating city', and when it blasts off from there. I think these would really help to make these shots look even better, and add to a sense of realism if they tie together more with the earlier platform shots.
That's your lot for now....my brain hurts!