Helm's Deep is a major major major point in the LOTR trilogy. Almost anyone can say "Helm's Deep" and your mind flashes to Haldir arriving with his elves, the uruks blowing up the wall, Legolas's shield-surfing move, and Gimli's "Toss me!" comment. But will the new update actually allow you to fight in Helm's Deep?
If it did, and I would pay a lot of TPs to get it if it did, then maybe the quest line in Helm's Deep could be split during the actual battle. After a quest, right before the battle, you could have Aragorn, Legolas, and Gimli standing in front of you, each with an identical glowing ring above their heads. Depending on character favoritism, a player could choose which character he/she would want to follow for the duration of the battle. Elves could pick Legolas (from what I hear Legolas is the reason many people pick elves), dwarves Gimli, etc. But it would be a completely voluntary choice. So however the update turns out, this is just an idea.