Though not a major game feature it would be nice to have a flight HUD. This doesn't have to be anything major just a set of indicators showing the ships pitch and yaw relative to the Astrometric Plane on display. They can be included in the mini map as a side instrument or a customizeable movible HUD feature. They show speed, ships pitch (nose up or down or level?) ,yaw (how it is tilted from side side) and altitude from the bottom of the astrometric plane to the ceiling.
These indicators would be handy for navigation allowing set it and forget it chat sessions and also for combat for captains who think 3 dimensionally and are trying to track how they are moving. Since the pilot is acting from a 3rd person veiw behind the ship this doesn't come naturally but instrumentation would facilitate this. It's a small feature that I beleive would really enhance the game.
These would be simple slider indicators that move according to what the ship is doing and it's position on the map.
Give each a label and a player will quickly understand what the indicator is telling them as they fly. They can match up their movements with what the indicator is doing and thus understand the meaning.
Though probably not a feature coming soon it would be nice to give the ships roll and loop abilities. Especially shuttles. I had some foundry mission ideas that involved atmospheric flying and those capabilities would really make those mission designs viable.
Again not a major game design requirement but it would really get some appreciation from some serious tactical captains and chat room junkies talking to Fleet mates.