As long as you don't mind the endless stacks of AS phalanxes which will eventually be naught but Klerouch and Agryaspides then sure. Any chocke point area is defendable. If you're using BI or later, beware, as the AI AS will target Cyprus a LOT. I'm sure if you're the human it will also be with ever-increasing potency as well. Plus the Punic side of Africa is not exactly overflowing with recruitment possibilities as the Ptolies. But its definitely doable if you want to try a new direction.