Tactics for playing as/against Barbarians.

In my opinion, Barbarians, with proper skill, are a very strong faction for some. But there are several drawbacks:

1) There is no unit that can cross the entire battlefield in one turn.
2) There are no flying units.
3) Weak magical abilities.
4) Weak defense.

But, of course, there are also main advantages:

1) Generally high attack and logistics for the hero.
2) 2 ranged units.
3) Good 2nd-tier units.

and so on.