SCH was nerfed during 4.0. They had weaker shields and more mana cost and barely any aoe dps, but then barely anybody play the job anymore. Even world first deltascape was done with whm/ast. Once sch shields become equal with ast, then other toolkit surpassed what nocturnal astro bring. If shield are stronger, it is easier survive certain mechanics. It is really hard balance between those two. I think nocturnal astro just need singletarget healing over time effect. Benefic 2 should turn into shield version like Adlo and Aspected Benefic should be regen regardless your stance.