I fully agree that he needs a rework. When I started the game before Navigator Eddie came out I thought he was the coolest looking Eddie and I wanted to get him the most. I'd happily use him if only he could be boosted to a proper 5* Eddie. As it is, his only gimmick is he has one of the highest cumulative attack stats in the game, at least higher than most other Eddie's. But with characters who have even higher power and better other stats, he's just a joke to them. I vote for a stat rework and a move rework as well.
But to be a little bit fair, he has a basic attack that grants him perfect immunity, so if you combine that with Steel Talismans he'll be invincible to most conventional attacks. Providing he gets the chance to set it up.