Well what size army are you going for? If you go with the combined arms approach of the 3 different types of Orcs, along with a couple of heroes, the metal scouts would be bearable as you wouldn't need too many.
Not to dissuade you though. The Legions of the White Hand are a good, solid force. Beserkers are just plain cool, and crossbows are one of the deadlier weapons in the game, particularly in numbers and they still get Shamans. Remember the humble Isengard Orc or Dunlendings though if you want additional numbers. And if you ever get to sieges, then you'll definitely have some fun with bombs and ballistae.
A lot of powerful heroes open to you. Any idea which you are going to build your force around?