The Battlerager helpfile leaves no room for soft goofies.
The Tablet and the War room stuff also urgely "recommend" to slay mages.

Seriously, you can't trick it with your role.
If battle imms would like to see peaceful ragers they should change the cabal ideology. Until then you can only balance at the edge and be "lazy" at killing good mages.
Not killing goodies is not valid battle role as it stands now.