[Xrati]

XP's should be based on the entire battle for a percentage of the base points of that specific battle (planet, base or open space, etc.)with different values for each.
1) enemy ratio ships to yours.
2) enemy ship size vs yours.
3) damage taken.
4) ships destroyed.
5) ships captured.
6) ships lost.
Each catagory would provide a percentage of the base XP cost of a battle. Where the total might not add up to 100% of the XPs awarded for that battle. (I hope this make some sense?)

I beleive what they tried to do with the scout ships returning to a supply point is to reflect the food/perishables that might not be found in any other form. Unless you have replicator (STNG) tech, you will need food and water along with necessities.