So, let me first say why I think Isengard should be improved. I find that, in general in the mod, evil factions are less developed than good ones, specifically orc factions like Angmar, Mordor and Isengard. Moreover, as other evil biomes are pretty sinister and menacing (Dol Guldur, Mordor and Angmar mostly), I'm somewhat overwhelmed when I enter Nan Curunir. Thus, I would like to suggest a few changes to both the biome and the faction to develop Isengard and try to embody the destroyed and corrupted vale depicted in the books and films.
I draw my inspiration from descriptions of Nan Curunir in the Fellowship of the Ring and the Two Towers; I also depicted these proposals thanks to adaptations in the films and video games set in Middle-Earth. To me Isengard should display corruption, industry and devastation (how it was transformed under Saruman), as well as a busy and organized place.
What I think would primarily make Isengard more interesting is the addition of structures. They would both add to the biome itself, capturing the corrupted and industrious atmosphere of the Vale under Saruman, as well as serve real purposes to the faction, for looting, trading and more.
Orcs are known to thrive in deep and dark places. This pit would also serve for mining; the remainder of a forgotten mine used to extract iron and make orc steel, arming the Uruks with their weapons.
This would be a fairly common structure in Nan Curunir, almost as common as an Uruk camp, but the loot would be mediocre. 3 Isengard Snagas and an Uruk would spawn at the bottom of it.
It would be about 8 to 10 blocks deep, growing smaller as it got deeper. It's sides would be made of Uruk bricks, dirt, stone, and maybe charred wood (all those cut trees had to be used somewhere). The bottom would feature scorched stone and waste blocks, on fire. The pit would be surrounded by charred wood fence, and a ladder would climb to the top on one of the sides.
I was thinking there could be an orc forge at the bottom of the pit, with a chest halfway down. It could contain iron/copper/tin ore, plus the usual orc items (maggoty bread, coal, sticks). The loot would be slightly better than that of an orc tent.
Tolkien described Nan Curunir's former landscape being replaced by pits and forges, and Isengard itself becoming an industrious producer of steel and death. Therefore it seems only fitting that a full forge structure would replace those small forge tents found in Uruk camps.
This new forge would be a semi-rare structure (similar to the occurence of Elven smithies) and would be made of Uruk bricks, with a slab roof held up by charred wood fences, with a large hole in it to let smoke out. Openings on either side would be covered with Uruk steel bars. At the back of the forge would be a lava pit, and orc forges on either side, while to one sides of the structure would be a chest, and on the other an Uruk crafting table. There could (possibly) be weapon racks on the walls, bearing Uruk weapons.
The loot in the chest would be considerable, being mainly weapons, armour, orc steel and Uruk steel. This could be the evil equivalent of Elven smithies, equipping players with the destructive capabilities to kill Rohirrim and Gondorians.
Like smithies, this forge would contain an Uruk Smith (unheard of, I know!). He would sell Uruk weapons and armour, as well as the odd Dunland chestplate or Uruk steel bar, and would buy iron ore, coal, orc steel, Uruk steel, oak logs and iron ingots. This would, in my view, solve the problem of limited orc traders, and give evil players the chance to use their looted coins.
Have you ever wondered where orc-draughts are brewed? The morgul-shrooms required to make them are found in Mordor, but we can safely assume that Sauron was kind enough to ship some to Saruman in Isengard.
The Uruk brewery would be as rare (if not rarer) than the orc forge, and would be built out of Uruk bricks with a roof of charred wood slabs. Inside it would contain three empty barrels on either side of the 7 blocks-long structure, with a chest at the end. It would contain mostly orc-draughts, allowing evil players to restock their supplies, and possibly have some maggoty bread, rotten flesh, and a bucket.
An NPC would spawn there: the Orc brewer. Resembling more of an Isengard snaga than an Uruk, he would sell orc draughts or varying potencies, and would buy morgul-shrooms, bones of all kinds, water buckets, and mugs/waterskins.
This brewery would further emphasize the alliance between Mordor and Isengard, and highlight the industrious nature of Nan Curunir.
This last proposal is not an orc one. Before Saruman made Isengard his home, it was a fortress built by men, with the tower of Orthanc at the centre. Therefore I think it would be fitting to add small, ruined turrets to remind players of the corruption of the fortress.
While I didn't build one myself, this turret would resemble Gondorian turrets, except made of stone bricks, with missing blocks and waste blocks surrounding the structure. There could be loot in this structure, or there couldn't be. I leave it up to the modders to decide, but if it did contain items, I'd say it should have Gondorian or Arnorian gear, as well as arrows, crossbow bolts, leather and coal.
So, the reason Fangorn is a sworn enemy of the Uruks of Isengard is because the orcs started chopping it's trees to fuel the forges of Nan Curunir. But looking at the biome as well as it's neighbour, the Uruk highlands, you'd wonder why. They are filled with trees! Maybe I'm missing something, but in my view, those two biomes should have their vegetation significantly reduced.
All in all, I think these changes would improve the experience of evils players crossing the region, and would make Isengard a stepping stone before heading to the dark lands of Mordor. In addition, I think they'd add to the realism and story of Middle-Earth, and to the atmosphere of Nan Curunir in general.
I hope you consider these proposals and make any suggestions to improve. Thanks for reading!
First off, Isengard at this time mainly used Dunlendings, the Uruks were likely hidden away being bred. Second off, for the most part it was Skinbark's people who felt the axes of the orcs, not Fangorn proper. Isengard should use Dunnish troops with Half Orcs supplanting them with the Uruk-hai being used as elite, not the broad as daylight troop they are in the mod. I will link a suggestion that suggests how from what we know how Tolkien envisioned it. Though I the structures, I think they should spawn in underground "cities" where Saruman his away his uruk hordes.