Why is it just fine to have so many abilities and spells that don't interact with the job gauge, even though you have access to it from level 2?

Vercure, Verraise, Fleche, Contra Sixte, corps-a-corps, displacement and Tether all do nothing with it. Tether, Corps and displacement may be forgiven, but Fleche, contra and the support spells being completely isolated from the job's main mechanics just feels off to me.