Another possible feature I can think of is the introduction of raid bosses as event boss. As long as you keep sortieing to the event map you'll eventually contribute to the overall score and rewards will be given to all participants. Even the ranking can be replaced with monthly raids, though it wouldn't mean much if the devs still limit their rewards to the top 500 rankers.
It's funny you mention that, because that was something that the GoGames version of KC had:
2x per day there was a massive raid where everyone could participate. You sortied your fleet and there was a fight against a single enemy that consisted of 1x shelling phase (the bosses last attack always did max damage against all ships and there was nothing you could do about it, but you didn't have to repair/rearm either so...). The damage you did chipped away at the boss' HP guage. There was a short cooldown before you could hit the boss again (I think it was 20 seconds) that you could bypass with cheap in-game currency that you could earn by logging in or paying a little real-money for.
Rewards were handed out to everyone in the top 100 (small audience, there were usually less than 50 even playing to begin with), but better rewards were for those that got in the top First, Second and 3rd damage and the person who got the killing blow got something too.
Overall, the rewards weren't huge (ships and gear that was rare/uncraftable but not game-breaking), but at the same time, these also ran 2x per day every day too.
Either way, a sort of 'Raid' system would be really neat to see here as well.
It just hit me after hitting 'Post' was that maybe that is what the 'Friend Fleet' system would allow? I know that there are several games that allow you to attack a boss/target with in-game 'friends'. The boss attacks/acts on the individual participants through the normal combat cycle, but the boss' HP bar is shared.
Maybe this is something that they are looking to impliment in the future?