First or the rest? Shub-Niggurath or the Strogg?

well OP, i think the world of Middle Earth would be much to large to fit into a single Bethesda game, especially considering we have very little information on some locations such as the kingdoms and locations located to the North East of Mirk-wood..
actually, if they wanted to keep it lore-accurate, Moria alone could be a game itself the size of Morrowind...
I am guessing you are going off the movies and not the books...
Orcs were not dumb.... this is why numerous Orcs sided the Saruman instead of Sauron cause they decided "you know, I think this Maiar would make a much better overlord then the dark lord..".. Orcs in LOTR were created by capturing and torturing elves, and their corrupted offspring became Orcs.. not to mention Orcs were extremely deadly warriors in the novels..
and if you read the extended lore, Tolkien talks about most races and their history.. he really didn't many out.. we learn of the creation of the Orcs and the Warg, the history of the Maiar, the acts of the Dunedain (Later to become "the rangers of the north"), the corruption of the Barrow-Wights, the eagles, how the Morgul blade turns people into Cargul, etc...
the only race he really didn't explain much about was whatever Tom Bombadil was.. all we really know about him for sure is he predates the elves... some people have some awesome theories though...
Yeah I believe that they were talking about doing the GoT game but they wanted to work on the Elder Scrolls instead, not to work on an ip they don't own or whatever it was.
I hate it when someone misses the joke completely.
I know. In looking back it wasn't a very good joke. Some days peanuts, some days shells.