Good afternoon, Heroist.
And a good day to you too. ;)
I had another idea – to create two versions of the mod: a single-player version and a multiplayer version. The idea is a bit far-fetched, but I imagine it like this:
In single-player, we nerf the warcry, buff Banshee, and leave the aura.
In multiplayer, we leave everything as it is, but remove the aura and (maybe the fear effect).
The idea isn't the best, but the respected Nargott is right that single-player and multiplayer are things that can't be compared.
If in a battle against a dumb AI, the ability is a terrible overpowered thing, then in multiplayer, it's a good chance to stay afloat.