I think AGS could easily use leaderboards in a way to either reinforce that balance is good, or show that balance is bad.
If you look at pvp leaderboards for war and opr. You can see how many of each weapon is in the top 100 damage and top 100 kills. If it is pretty dominantly 1 or 2 weapons that could indicate a lack of balance. Or if a type of weapon has all damage but minimal kill potential.
There are obviously certain variables like player skill level or type of match that was scored. Even with those taken into consideration if it is quite lopsided would be a good indication on where to look for adjustments.
Just some thoughts I was having. Happy Merge Day!