I grew up reading Tintin comics. Wikipedia has an interesting observation about how the “blandness” of his character lets the reader place himself in the adventures.
Readers and critics have described Tintin as a well-rounded yet open-ended character, noting that his rather neutral personality—sometimes labelled as bland—permits a balanced reflection of the evil, folly and foolhardiness which surrounds him. His boy-scout ideals, which represent Hergé’s own, are never compromised by the character, and his status allows the reader to assume his position within the story, rather than merely following the adventures of a strong protagonist. Tintin’s iconic representation enhances this aspect, with Scott McCloud noting that it “allows readers to mask themselves in a character and safely enter a sensually stimulating world.”
I had never thought of blandness as a benefit but it makes sense; it makes me think of how in designing user interfaces, you don’t want the user to notice the interface at all–you want it to disappear, so they can get on with what they are doing.
It also reminds me of something one of my teachers once told me–she said that if at the end of the class, people told her she was amazing, she hadn’t done her job. If she does her job, the students are amazed and excited by their own discoveries and learning–not by her teaching or skills.