I don’t really need western weapons to be better than eastern weapons, or vice versa. Your choice of weapon should be based on what you find, what martial art styles you know, and personal preference. If you personally think that jians are the best sword ever, I would prefer that the game not make that a sub-optimal choice.
The specifics of the situation that you are in might mean that your preferred weapon isn’t the best - a no-dachi should be the right choice against slow, armored targets, while a broadsword is better against fast, less armored targets. But broadly similar swords should be equivalent in raw numbers.