Used with a strict parcimony for few units this option would be nicely historical and would simplify the things. Saying, I'm a Roman strategos or a french lord, I need genoese mercenaries, I speak with a merchant(a genoese banker parasiting my economic system obviously), the dude contact the mercs and arrange a contract, and few weeks later I have my company of elite crossbowmen ready to join my army...totally historical. Because actually, if you need mercenaries who historically fought at your side, you need to go in their countries, in a crappy tavern full of drunken and harlots. Completly pointless, do you imagine the king of France forced to go in a genoese tavern for hiring genoeses when a lot of them are graviting in his court or live in Paris...???
So, the Lance system is fully accurate, yes, out for "exotic" mercenaries.