I like it.
It looks a lot like my Dol Guldur army in several areas, and I admire how you're keeping to theme while working at a competitive force. That being said, you DID ask for input.
Make sure you give your Goblins and Orcs shields.
I'm not 100% sure if your Wargs are wild wargs or warg riders. I think Wild Wargs and they are my preference most of the time, but if you have the points to draw from on allies then you could always up them to Warg Riders with shields for a little extra defense at no real loss while gaining Thrown Weapons as well.
Get some Ghostly Legions in there.
The Specters are great but having a couple 3-4 Company Formations of Ghosts as well would keep some of the attention off the greater threats and give you some nice infantry to Spirit Walk right thru terrain or other formations to secure a flank or rear charge, and the more Spirit Grasp forces you have the better too. My Dol Guldur army ate Dwarf and Elf armies for breakfast when we were building them during a local Tale of Gamers thanks greatly to Spirit Grasp (yes, Captains/Heroes are in there but they are STILL lower Courage than some of these model's Defense). They are all plastics, quick to paint and the extra points gives more to allies if needed.
Shades. Oh yeah. With Epic Strike being a threat a couple Shades zipping around keeping everyone at a nice Fight 2 levels the playing field greatly. Now you don't need to care about having a Captain in your Ghosts for At the Double, because he's as good of a Dueler as most Heroes now.
And as a final suggestion, I think you should definitely play as an Angmar Battlehost. It will cost you a little less than another Shade but they are one of the BHs that really benefit their force. You already selected the Tainted so it will give all BH Formations within range +1 Strength. AND, best of all, all your BH Formations and models in it are immune to the Shade's effect (if within range). So now your Nazgul could call an Epic Strike, F10 against any other Hero at F2. You are +8 before the first die is even thrown, if they are foolish enough to take you on.
Go Spirits of Evil!!!