I think it's safe to safe the planet generation will be sufficient so it's really down to getting the flora and fauna right but....we also want stuff to do on these planets and this is where things might be just too big to do. How do you make engaging content if you're using RNG all the time? Is it possible to make plants and animals look different on each planet. Will FD have "M Class" planets with just algae as the only life form on it (remembering that for the first few billion years, earth had no life on it at all and then after that it was just bacteria for ages). I'd like to see complex life being a really rare thing and mostly bacteria/algae for the most part (bacteria with the scanner they'll make so we can catalogue these things).
On top of that space stations need massively fleshing out and they need to use PG or RNG like warframe does. Let's have RNG placed crates in the hangar bay. Let's see erosion if the station is really poor. Power Play needs to be expanded to be a much more prominent thing - let's see the effects of war, let's see us joining these factions we fight for so we actually feel something for them.
FD already put things into the game and I think that's a great way to do things. Injecting stories like a DM does in Dungeons & Dragons is probably the best way to keep the game alive. This is where having a massive universe is now beneficial as you have so much room to play in you can literally make up infinite stories and place them anywhere around the cosmos.
Thargoids - shouldn't see them for years as that should be a story that's built up over time culminating in a huge battle across space as they surprise attack us, taking out stations out on the rim. Desperate calls from civilisation are made to the Pilots Federation to get to the front and try and defend against the horde but they're too strong. By this time, FD will have made walk around ships with Hi Fi damage modelling and an engineering station Geordie La Forge would be jealous off. You fought a good fight but the thargoids were too strong.
All around you are the wrecks of AI ships, torn in half but then, over the crackling comms you hear a voice. It's another Commander, he's asking if anyone is out there. start heading back to the cockpit from the engine room. As you make your way, more voices come over comms - more commanders calling in. One by one you all realize that many of you survived but you all need to help each other out.
You all manage to limp to a close by asteroid, using it for shelter. Through eva and swapping parts, you have enough to get a few ships operational again and send them off to get help. As you wait, you're all repairing your ships as best as you can until other Commanders show in their "tow trucks" - specialised mechanics with loads of parts on board. They stop off and with their superior mechanic skills get your ships fixed way faster than you can do it. The ones they can't fix they tow to the nearest space station. You fly back with your wounded comrades, making for the bar after you land. You meet up with other commanders, everyone's talking about the battle, everyone is wondering how the thargoids can be defeated.....