Aetius and the Western Empire

[starman2012]

The Ostrogoths were also a great problem until they moved West in the 6th c.,

Around the end of the fifth.

and let's not forget the Isaurians, the Persians

In the fifth century at least, the Persian front was quiet--certainly relative to what had transpired in previous centuries. Had there been major fighting there, precluding the interventions in the early 430s (Aspar), in 441, and in 468, historians would probably say Persia prevented the East from recovering North Africa hence was indirectly responsible for the fall of the West.