[Facts] Re: Argantael and the Old Breton “hael”
Generous is an adjective, Prince is a noun. Not the same word. As an adjective hael is modern Welsh. As a name element it is cognate with Gallic -sagilos. The root sag- seg- and ablaut variants produces a large number of elements relating to strength and victory (not only in Celtic but Germanic and Greek). And yes many are feminine.