If they keep following the kind of AoE damage they designed for Alexander: Gordias, the range "issue" will be nullified. In A3S, for example, it takes more than a Medica II to heal through some heavy AoE damage mechanics, which means that even WHM requires the party to stand within 15y – Medica and Assize aren't 20y, it's a Medica II thing. This means that AST is perfectly fine in relation to range.
