No reason you can't use orcs models as uruks. The board is 2' x 2', and the three hunters have 7 turns to get Aragorn and one other model off the edge of the board opposite the one they started. The hunters only have 1 point of Might Will and Fate each, though Aragorn has his free Might point per turn.
In their way are 8 scouts with hand weapon, 4 scouts with shield, and 3 with bows. If you wanted to use actual orcs, points equivalent would suggest another 33% orcs, but that might change the dynamic of the scenario and make it easier for the evil side to just get more models in the way.
Thinking again about how I introduced my friends to this game, I set up a much smaller game first, with 6 or 7 troops on a side, 1 or 2 elites (so Fight values matter), no heroes, to the death. Two warriors, 2 or three spears, two bows. This takes care of all the basics covering each Phase, but only takes about 1/2 hour to run. Then I did the above scenario.
A third option I used recently for a rule refresher. We're an older crowd (nearing 50...
) and each of us has the game we prefer, so one will host WW2 stuff, another American Civil War, another micro armour...and me with LotR. They are least familiar with mine, so each game I set up a small mini-game prelude to go over the basics. Here's what I set up most recently:
Board: 2' x 2', with 6-8 small pieces of terrain (small rocks, single trees, etc)
Good: 6 Warriors of Rohan (2 with shield, 2 with shield + throwing spears, 2 with bow), and 2 RRG with throwing spears.
Evil: Sharku on Warg, 6 Warg Riders (2 with shield, 2 with shield and throwing spear, 2 with bow).
Story: warg rider scouts have accidentally ended up behind enemy lines, when discovered by a small party from Rohan.
Objectives: There are no victory conditions, and rules for Broken do not apply. The Evil side must get as many Warg Riders off the opposite edge of the board by the end of turn 4. Any warg riders (including Sharku) who don't make it will not be useable in the next battle.
You can see the Good side is totally overpowered, by design. The point is to cover all the phases of the turn, refresh how Fight score can change things, getting shooting and throwing weapons on there, introduce a likely need for Might should Sharku get trapped and lose priority, and keep it short