Hey Dave,
Wow, what a pleasure to work with Jupiter so big in the frame, like Matty said, it was fun to play with some quality data.
The main thing I did was use the unsharp mask in gimp with values of:
radius = 2.5
amount = 7.5
threshold = 0
with 146 frames stacked (from the big zips) in registax separately as r,g,b and then recombined in gimp and unsharped.
Here is my effort at processing, with my newbie skills, not sure if it's any good, apologies if it looks worse
. Comparing them side by side, I prefer yours.
Chris