Well firstly, ditch the stupid highschool shit. Highschool is piss easy. Adult life comes with far more responsibilities and commitments. Have him deal with student loans from trying to get a phd on a photograph salary. He pulls all nighters and is irritable. He has shit loads of horrible dates he chooses to end because it asks too much from him.
Peter isn't outdated. Nothing you do with a new character you can't with him. He's suppose to be the everyman, but what that is changes. So Peter should reflect that. Or ditch this pretense of realism and let him be a chad in his heightened reality on a heroes journey.