I know a two tier buff will do the job, wasteful.
Has anyone successfully done an ability with applybufftoself that autocasts based on shield conditions? I can't seem to manage that feat without using a targetted buff, which then casts the buff on itself based on some other ships lack of shields.
Second non-wasteful possibility, can you create a targetted ability that only targets self? Self, or IsSelf, doesn't seem to be in the list of constraints.
I'd much prefer to avoid mucking up someone's mod with an unnecessary entity where two should suffice.