The Disciples of War and Magic are all useless after you upgrade to a job. No one plays them (at least from what I've seen). There is no reason/need for them. When we get to 30 we all go from having a class to the job (or jobs for arcanist) and never look back.

What I think we need is something, a trial or dungeon of some sort where it will be needed to play your class over your job. It would add a little bit of something that we can do with our class then just stick a soul stone to it and call it a day.