1. Increase the to-hit distance of the weapon (It's the longest 1 handed weapon in the game so the distance from the monster to hit should be longer then the Khopesh!)
2. Add a damage enhancement with Bastard Swords/Longswords for Humans. (The Bastard sword is built for damage NOT crits so this should be reflected)
and Humans don't have a weapon spec enhancement line but other races do.