The Beyond series was great - especially chapters 1 and 4, because they really improved upon already existing core gameplay mechanics of Elite Dangerous in a fundamental way, exactly like Frontier Developments promised it. Combat wasn't part of the Beyond series of updates, but since that was tweaked and updated in every update before Beyond, I think that's in a pretty good shape, too.
What still is in dire need of improvement, IMHO, are the following points:
- First and foremost: NPCs! There are so many NPC related features I would love to see in the future - NPC wingmen for hire, NPC crewmen visible in their seats, some degree of NPC persistence being the first that come to mind
- Multicrew! I would love to see additional, preferably non-combat orientated roles for multicrew!
- New and additional SRV types. The Scarab is nice, but more variety on planet surfaces with some more specialized "Buggy" types would be awesome! (a hauler vehicle with more storage and less speed, for example)
- Dynamic Capital Ships and Megaships: I always thought those badass looking Capital Ships just being static waypoints or being warped in in specific CZ or scenarios at some predefined point was very lame and a waste of those cool assets. Instead, I always hoped of them being real ships flying through the galaxy. Specific Capital Ships should only be encountered in the systems they are really at that specific moment of time. We should be able to see them fly through supercruise and even make hyperjumps between systems. All superpowers should have designated fleets of Captial Ships that represent where they focus there power at every given time.
- Additional ship launched vessels about from just fighters. Like many others have already suggested: I would love to see "Ship Launched Miners" or perhaps even "Ship Launched Recon Vessels" for explorers that could separate from the mothership and are able to autonomously surface scan/map planets while the mothership is mapping another planet ("divide & conquer" for system mapping, so to speak)
Apart from that, I would love to see Frontier continue their efforts to better integrate the existing features of the game, as they did with "Deep Space Mining" in Chapter 4 (integrating Exploration and Mining, for example).
I would love to see Powerplay be better integrated as an intermediate layer between Minor Factions and Super Powers in the Background sim, with similar kinds of activities for supporting all three of these layers, for example.