I have two concerns when it comes to the Western Roman Empire:
- Are there enough Roman/Italian people left in the Italian Peninsula to make a functioning, unified country?
- Are there enough upper class people willing to endure the hardships necessary to make a functioning country as opposed to relying on foreigners and corruption to keep their lives comfortable?
Also, despite the best efforts of people like
Majorian and
Anthemius, I don't think Italy + North Africa had the ability to maintain Roman control over Gaul and Hispania. Finally, if Egypt falls to the Muslim Conquests, I suspect a weak West cannot defend North Africa.