I disagree that not killing good mages is incompatible with the cabal. I've even had Leader-to-Leader sit-downs with mages over a cup of mead, and that was as a neutral. A good rager might have even more reason, specifically his common alignment, to find a non-murder way to do battle with a good mage. Come to think of it, the Rites of War aren't just a battle royale. There's a non-murder Test of Wits too.... right?

From another perspective, mages expect ragers to attack on sight. Not doing so shakes things up a bit, and can actually make things a little interesting.

Now, if good rager doesn't show up to defend when good mage raids, that's probably crossing the line. Similarly, that line can be drawn in different places, based on the Commander at the time. A fire giant who hates elves probably isn't going to let a pacifist-toward-good-mages elf rager stick around too long. On the other hand, realizing that there is an exploitable benefit to having this type of rager in your ranks would be a characteristic of a great leader, in my opinion.

The short version is, there's wiggle room everywhere and I like that characters can exist with some form of conflict between morals and cabal. It is (and should be) possible to walk the line and make it work. It is (and should be) possible to stray too far to one side or the other and face consequences. The line is not (and should not be) static or easy to define.