Adlo changes aren't needed. The reason for the shield disparity between Noct AST and SCH is due to the fact that SCH has a 1700-2100 free HPS bot flying around throwing around hundreds of thousands of HP worth of healing and freeing up dozens of healer GCDs for dps. SCH hands-down, even in it's "nerfed" state, has more output than any other healer is capable of doing in raid setting sans balance. Noct AST's shields are pretty much novelty compared to scholar utility and practicality.