Adding more underepresenting weapons won't change a thing. What needs to be done is the already implemented weapons to start to change subtypes, so that the elite subtypes will be rare(as intended to be) and not very common.
When builders started adding up too many khopeshes/bspears/kamas/etc in SK, things went down when it came to balance. Khopesh for example, being one of the best 1 handed no reach options of the game(the other is kama, but as an exotic it has other penalties) was really limited when the weapon subtypes were implemented. Actually, up until 2.5-3 years ago, there was only 1 adamantite khopesh out there, 4 copies of a mithril one and the rest was tanso or lower quality.
What happened since then?
Every good area must have a good scripted weapon added. This weapon of course has to be an elite subtype. So we have HP regen water khopeshes, we have an HP battery diamond khopesh, we have generally TOO many khopeshes. Not to mention whiney players bitching to their buddy imms to change weapons to khopeshes and suddenly this happening(*cough* energy archangel swords *cough*).
So now that there is an abundance of khopeshes, it's obvious that everyone will try to use them and spec in them, because it's so easy to get his hands on them.
So refer to my signature.
PS: When A'van was getting revamped the first time(not when wert tried to), I got to see all the lewt that was added to it even though it was a restricted area(<3 teleport). What I saw was full adam suits(that SK doesn't need any more for sure), tanso khopeshes on lvl 35 NPCs and generally more phat lewt. Thank god all the changes were reverted, else we would literally see every merc in SK dressed in full adam with a khopesh, without worries about spam dying because he could full re-equip within 5 mins with more adam and a new khopesh.