Unfortunately, Ethan's malnourishment will prevent him from being able to output his full potential. Ellis, on the other hand, relies on his suit to maintain a number of bodily functions, minimalizing the amount of energy he must expend. This leaves Ellis with more biotic ammo than Ethan.

Ethan's physical capabilities would fare badly against a suit with the strength of a krogan, so once his biotics failed, he'd be hard pressed to survive, let alone survive without horrible psychological scarring.

I just reread both Character Sheets. I gotta stand by my original observation.