The problem with Warfare and Rune is that some of their Skills seem to overlap each other, especially:
Onslaught Tree >< Rune Weapon Tree
Dual Wield >< Reckless Offense
So if you noticed players seem to stay away from this combination. Most people tend to play with Earth or Storm: First to benefit from the Elemental Damage, secondly to have a real Spell to cast on Monsters (Rune doesn't offer a real Spell)
About playing a Berserker Ranged, well you’ve said it yourself, I hard to see how Warfare could help in the matter, maybe except for:
- War Horn > Doom Horn: the range of the debuff is really wide when you max the base Skill,
- Battle Standard > Triumph: for the +Skills obviously , the Reduction in Energy Cost, and the Debuff (thanks to the synergy). The area of effect of Battle Standard is even wider(12 meters).
Still! Warfare contribution for a Ranged Build seems pretty minimal to me. This is not to say Warfare and Rune don't go well together! I feel it's quite the opposite, I've got the hunch playing a Melee Leroy Jenkins as a Berserker is a pure blast.
It's just that I'm not playing a Berserker right now, and people in this Community have not reported a good Berserker build yet.