I think he'd be good at nudging people, trying to fix situations like he'd fix a broken watch - finding what's out of place and trying to coax people into fitting in with the rest, all working together in harmony. I could see him starting in that cafe - with the young man and the owner and the barista, then expanding slowly as he kept up relations with those people and others, as they became his surrogate family. When they moved, he'd still want to know what was going on with them, because he knows them. They're his friends, even if they don't know who he is. And I think he would live through them, listening to their troubles and trying to figure out how they live their lives, and how he can live his. Maybe sometimes giving advice or removing obstacles for them, but very discreet, very subtle.

He's been betrayed so badly and so many times, I think he'd be very comforted to interact with people from behind a mask, so they never knew the real him, his horrible past, or his inhuman abilities. Instead, they'd see him as just another normal person.

I think Peter would check. He spent 5 or 8 years trapped with the guy. He knows Sylar's problems and his powers. I don't think he'd let Sylar be unattended. Or too lonely, although Peter does have a tendency to get tunnel-visioned. Ha - I can see Sylar keeping up with Peter for the same reason as the other people - keeping Peter 'fixed' and working right.