Well, actually, the way I picture Tanner, I don't need to change his personality, because the PB fits it now, moreso than it did. His whole young life was filled with nothing but school, trouble with his father and then taking on part of the responsibility of the family's welfare. So he was an A student and went straight to work after school and did his homework when he got off of work and then to bed. No time for anything else. He's smart, responsible, serious, but not morbidly so (he can be teased out of being so serious)...and he's a bit shy. As far as relationships and sexual feelings, he's batting zero in that department.