I suggest that there be additional single-player missions, or scenarios similar to elimination games made with pre-set enemies. Similar in nature to Starsector's missions or Beseige's main campaign where you're presented with a problem, and in Starsector's case you're given the tools you must win with, and Beseige's you must construct your own solution.
Given that there's now a massive library of high quality in-game ships to select from, these missions can easily be arranged. Missions could serve as an alternative to the campaign for single player game modes that are additionally easy to rapidly get into without having to play an entire campaign, and would allow for high-level gameplay without stakes or a wait time attached to opponent players.
The tools that would be established with missions would also allow modders and those seeking to implement their own factions to easily display their custom ships and show what one might encounter should they play the campaign with the faction mod, instead of one requiring to manually load the ships into game or to wait until progressing through the entire campaign to see the higher end ships. Even simpler than that there could be custom challenges people could theoretically share on the workshop.
If lore or story are sought after these missions could easily be representative of past or current events, whether it be an important battle, scrappy border skirmish or standard patrol, similar to how Starsector was capable of helping establish the setting before the player even starts the game by having text accompanying these missions.
Finally missions can also serve as an introduction to simple combat tactics, such as how flanking can allow otherwise outgunned ships to win, or how kiting can be very important when it comes to determining victory or defeat. It would be a great way to better ease players into multiplayer, where difficulty can become a wall if there's little to no practice or experience for the average player.