"Cabal XP" was never intended to be an efficient means of ranking. I hope that's evident. But considering that participating in cabal wars is usually obligatory if you're caballed, then getting XP for doing so can serve a dual purpose.

If your primary objective is to gain levels then ranking is the way to go. This specific change wasn't meant to change that, but rather make that fringe benefit of doing what one is already probably supposed to be doing a little better, especially if/when proper ranking isn't viable.

I don't know about the characters you listed specifically, but obviously if someone is deliberately trying to avoid getting XP to "level sit" then yes, this change doesn't interest them much and that's fine. If someone really doesn't want to level up, they can always go mob die, suicide, etc.

I'm not particularly worried that this change is going to encourage people not to raid/retrieve. If someone were avoiding cabal wars solely to dodge the XP, that may very well be crappy cabal RP and a cabal IMM could step in and heckle them for it, too.

I think you're right though in that you probably didn't get the point of the change. It was one of many relatively minor tweaks to help increase the over all pace of the game, that's all.