I'd love to see a lifespan modifier. Have it affect commander health,retirement,death,promotion. Unless you storyline a commander, it seems impossible for them to earn much in the way of medals if you use realistic promotions. If they have a longer lifespan/career, they can spend longer per rank/assignment to earn those high level achievements.
To go with this, maybe a way to modify how many of a lower rank is required before a promotion is available. Instead of taking 10 ensigns before promoting one to Lt(jg), a way to change so its 15 ensigns before promoting one for example... not sure off the top of my head what the current ratio is & I know it's out there cause I've seen it, but I think you get the idea. Or maybe add a minimum promotion points required for each rank in addition to number of lower ranked officers to trigger a promotion.
That top level commander should have a full salad on his chest, right now, with realistic promotions, that just doesn't seem to happen unless you storyline & micromanage.
Another thing that feels off, shouldn't all commanders on a ship get the credit for discovering a star system for example, and not just the ship captain? Or at the very least, those assigned to relevant jobs in addition to the commander