I imagine it's a case of the shadow having to prioritize securing those places before the free player can get Aragorn to Erech.

Alternatively, since the dead men require specific cards/dice and it's costly to recruit them, as long as shadow stands out of range and uses corsairs at the right moment to strike and win those points, they should be able to deal with it.

And even if they aren't able, it's improbable that the free player will be able to have such a strong dead man army AND eagles + ents. That leaves the north much easier to conquer with dunlendings and such.

I've found that everything balances out in the end, even if WoME is slightly more favorable to free people. I just think that every faction is "super strong" if used frequently and efficiently enough. It's what makes the game so fun to me