"Lighten up, Francis" - Sgt. Hulka
Personally, I try and be objective (a contradiction by definition, I know) and consistent, meaning that if I critisize X for embarrasing themselves by doing something, then Y, doing exactly the same would also be subject to my critizism.
Now, some people revel in seeing J as arrogant. It reinforces their own perception of the man - confirming ones prejudices is everyones favourite. This means it's hard for J to do anything right. Same goes for Marie. If you percive her to be disinterested, then you'll always look for signs of disinterest or even make them up in your head (preferbly reinforced by a picture of her blinking... I mean, obviously so bored she fell asleep).
And as you say, if someone for some reason, cares for a person (let's say F), they'll forgive him anything, usually attributing things to "folksyness".
And sure, they all have faults. But objectivity and consistency demands that social dogma applies to Peter as well as to Paul.
To charicature - J should recieve the same critizism for drunk driving, as F would (and vice versa). It's not a valid argument in a debate to "like" someone more than anyone else - hence my appeal for consistency.
Keep your chin up.