Ok, just got through playing my first game of Rebellion and I noticed two things.
On an asteroid I explored the planet and found "Expert Crystal Miners". Strangely, like other things found from exploring, the asteroid did not get the little artifact indicator and it also did not show up in the research artifact screen. I don't know if this is by design or what, I just found it strange that everything else I found from exploring had those things and the Expert Crystal Miners did not.
Second, the missile batteries on the Sova class capital ships. The stats between each level are the exact same, there is no progression. Does it just let the ship place more? If so it should say something to that effect. As of right now it looks like upgrading does absolutely nothing.