1. I think core gameplay that needs lots of work is working out a means of how to deal with scaling gameplay in the game to player rewards... in a way that leverages skill. Whether it's via difficulty in the same activities ...or a new activity that is simply more complex requiring a mastery of piloting ability, driving ability, or on foot ability.
2. exploration needs environmental hazards. (this plays in with 1)
3. Trade needs environmental hazards and position based risk centered around the BGS states of systems that actually matters (done in a way that is beyond the simple interdiction mechanism) (also this plays in with 1, everything plays in with 1)
4. Mining needs scarcity that is not simply implemented via lowering RNG yields. Mining needs the act of mining itself to be risky, and for that risk to be rewarded with higher yields and for the act of mining to "use up" what has been mined for a certain amount of time at least so that other players or other attempts by the same player can't simply farm a given area. Mining could be something as exciting as combat for those looking to get the highest yields or leisurely for those who dont care if it takes longer.
5. travel in the game needs to be part of telling the story. Not with artificial road blocks and tedium added to make things take longer or stop players from doing what they want, but like actual interesting and beneficial things happening during travel that allows the time it takes to get to places remain mostly the same but be the difference between a boring uneventful journey or an exciting and beneficial one that was say...harder and more active.
6. Focus on community content and back-end means of automating the submission and use of such content either via chosen volunteer groups or other means. Galnet and local system news should be overflowing with community content.
7. Give up on whatever narrative was going on and just go with the flow of the BGS. If the players have done something in the BGS that kills off aegis ..then kill them off in the narrative. If this means that humanity has no defense against the coming thargoid invasion, then give us the thargoid invasion without any easy "i win" option. if all our systems fall to this overwhelming thargoid invasion, then let it. If the players fail to win the cz's ...then kill those systems off. If in 6 months there's nothing left of the bubble then too bad.
Let the players decide the fate of humanity. If it turns out to not be something you intended for any potential future elite games, then just ignore the outcome and make up your own. Though, i think it's far more interesting of a space game (and games in general) when you dont start off with infinite resources and peace and end on that as well.