I can certainly keep the character raw and rustic even without being a teen. He won't be perfect by any stretch of the imagination. My idea for why he's around is that the institute needs a medic, and Logan remembers him from the war and has Charles find him so he can go recruit him. While he may be an adult, he is by no means completely refined or pristine personality wise. He's a lot like Logan in that respect.

But if that still doesn't work for you then I understand and will simply back out.