AST is very lackluster and while it may be fun to mess around with there is no way ever that ast will replace either whm or sch, you cant match either whm or sch at what they are doing by that logic why would i bring an ast which is meh at both over a sch which is the god of utility and mitigation or over a whm which is the god of group healing. Also ast/whm is much less viable than sch/ast due to losing supervirus covenant or sacred soil (talking bout progression)