Jables90:
The problem is that I need it to be powered by a single power source, ideally a standard 5v USB power bank. Therefore I need a solution to properly distribute power and have enough buffer when all modules run at the same time.
Post your wiring diagram so we what you have in mind.
You could use an LD33 / LD1117 to drop the 5v to 3.3v.
And try the batteries anyway just so you can be sure you are addressing the actual problem.
...R