One of the things I find most inadequate in Freespace is the radar screen. It just doesn't give enough info.
The first Space Sim I played (the one that got me hooked on the genre) was the original TIE Fighter, in the DOS age. I've never seen an in-game map screen quite as good as that one. My biggest gripe with Freespace and Starlancer is a relative lack of situational awareness.
What I want is a large map screen (called up as an overlay like in TIE fighter, or continuously shown on the secondary monitor of those who have one - after the DX8.1 upgrade this is certainly possible) to maximise sitational awareness.
It should be circular plane, centered around the player, showing the objects around him on their relative position, using a vertical 'pole' to display relative altitude.
Fighters should be represented by their icon. Capships as a model, hostile missiles as a dot. Colors would be green for friendlies, bluish-green for squadmates, red for enemies, yellow for incoming missiles.
There should be a zoom in/out control. Potential realism feature could be a maximum scan range, toggle-able to be displayed as a circle (on the ground plane) around each object with a scanner (or its anchor point on the plane). Sensor data would be shared between friendly fighters, cap ships and sattellites.
Another nifty toggle would be to show a health bar above each fighter and cap ship, RTS-game style, and have little icons to designate mission critical craft. If the screen real estate allows it, extended information (mission, speed) could be presented as well.
Of course, this whole thing is very ambitious. What would be a good start, I think, is to increase the current radar about 10-20% in size and show ships by icon, not as dots.