Actually, if she was a fullblooded Archangel (The immortal can use all class powers type), she could carry her rupture with her, thus allowing her to wander yet still use her powers. The question is, if Echo just wants to stick with weather only, why isn't she using her other abilities? Amnesia? They were drained by a demon? etc. 

All Archangels have access to all abilities, but typically specialize. Lucien, for example could use Tamer powers before he was infected, but prefered to use his Battle skills. His daughter, before she was executed, prefered to use illusions. But she could use rapid healing and other Battle skills. Before the Great War, every Angel was an Archangel.