More of a wish-list sort of thing, and not really in step with the OP, but I'd love to see more robust statistics tracked by Combat Mission and displayed for the player. Aside from win/loss ratio like the OP wants, more detail about the combat that took place in the debrief, and perhaps a cumulative page showing aggregate totals throughout the players 'career'.
For example
Rounds fired for each weapon type
Accuracy percentage for each weapon type
Most lethal weapon system
Distance traveled
Longest range kill
Average range kill
Penetration/deflection/part