Random Question. Do you let both units (i.e. crossbowmen AND Longbowmen) deplete their ammo, as the way your putting it that dosen't sound like what you've done. Re-run the tests doing that and i bet the results would change in the Crossbows favour, just becuase it's nearly even ATM.

Of course if you did let the crossbow men expand all their ammo, then ignore the above.