I found the movie to be intense with the tender emotions being very subtly portrayed. The characters have bold outlines, with kindness, acceptance and emotional strength in every scene.
Personally, I could deeply relate to all the main characters, especially Via, who is always supportive of August when his parents can't support him- like on Halloween- and is forever-sacrificing for him. Apart from the character of August, those of his sister and mother are very intense. For Via, it doesn't appear much on the surface, but deep inside, when you observe, she is battling as much as August is, only in a different way.
As for Julia Roberts and Owen Wilson? Who could have pulled off the roles better?
And of course, the role of August is perfectly played out- every action strewn in a burst of thoughtfulness and emotions.
I would call it a must watch, and I don't think I would shy away from giving it another watch (or a dozen more)!