I don't know if this has been mentioned before but it will be really cool if you could do that. In the real world its not practical because of the freezing temperatures and the high pressures inside a Gas Giant. But maybe in Elite dangerous where technology has advanced you could technicly say that they have that kind of technology so the ships could do that. The performance issues could be a problem or the fact that this might take a long time to be implemented. But aside those issues there could be materials that you can scavenge in Gas Giants or something more mysterious like another alien species waiting to be discovered. I am dreaming big, but if you could atleast fly through them, you could take some nice photos.