I will once again give my support to Mauhur as the scout hero. I just ended a couple of matches against Lothlorien, and I didn't really need Bill (ok, I played a bunch of matches because the AI kept crushing me down, but that's another story
). The point is, even if his last skill is really useful, he has to get level 10 first. If he reaches it by experience, it will take too much time, while if he reaches it by money, you would waste a lot of money for a skill only, which is something Isengard can't afford in the early game.
Trust me, in the Early Game Dunlendings are absolute beasts, especially if equipped with torches and sometimes escorted by Uruk Scouts, until you can overcome the EG by recruiting Wulfgar^^
(Atleast, that's my strategy)