As it stands now people only run Threnal for one or two things, the Cloak of the Worldshaper or Retribution (which I have not seen drop in ages, out of the game maybe?)
The quest series and giant caves used to be "the" thing to do, of course this was four years ago. There is an item in the series I always thought needed more expansion and versatility, The Threnalian War Blade, as it stands it's a +5 Blank of uselessness. It used to be a great thing to be able to get when finding a +5 random drop was a rare thing and you needed a couple extra to-hit when running Tempest Spine Elite and those pesky Drow Blackguards proved to be a bit hard to kill. Yeah I know, someone is going to say, can't hit Drow Blackguards? /reroll, well contrary to popular belief Tempest Spine was a challenge back then.
So my suggestion is this.
Revamp the Threnalian War Blade by adding crafting along the lines of Dragontouched Armor. Not adding disintegration guard or anything like that mind you but something in the level range. Basically allowing runes or sigils to drop randomly in all of the quests in the pack including the Giant Caves that allow one to add an enchantment from current randomly generated weapon mods to the War Blade. (Maximum of two, just like randomly generated)
Allow people to choose the type and metal of the weapon upon turn in of the quest requirements. As far as the metal type add a requirement for Ceremonial blade + cold iron ingot or adamantine ingot, silver ingot (which would drop in the chests as well, albeit rarely). Then onto the forge where the weapon and the runes you have collected go in and the character gets that nice new +5 weapon (BTC of course).
This would provide an option for those folks that always wanted a +5 Silver whatever but can't afford the insanity that is the Auction house.
As a side note since the pack is level 10-12 the weapon mods available to drop would be limited to the maximum capability of a ML 12 item, No need to allow people to craft +5 Silver Holy Burst Weapons of Greater Evil Ousider Bane, That would be so overpowered it's silly.
Just an idea.