Harad is a favorite part of the mod for me because of the depth and time put into it even though it's on the fringes of the stories and Tolkien's lore. So to add to its depth I have suggestions!
1. Tauredain Miniquest to kill lions and bring back lion fur for revenge against the Moredain.
2. Unique wildlife in the far Harad cloud forest (perhaps Leopard/Jaguar/Ocelot) to make this biome more unique as it is one of the most beautiful biomes in my opinion.
3. Tauredain Miniquest to bring them some dye of a certain color for their face paint.
4. Tauredain gold merchant. Merchant selling golden, nuggets, ingots, rings, armor, etc. Just because gold is very common in the jungle so why not?
5. Moredain sun warrior who is a hireable troop that is very expensive and requires extremely high alignment but they wield weapons which set enemies on fire.
6. Tauredain War Shaman. Hireable unit which is a medic, using jungle remedies to cure other hired units of poison, and also healing one nearby unit to full hp every 5-10 seconds. (Ok this might be really busted but still fun to think about).
Even if none of these are added it is fun to speculate and discuss!