Unlike the rest of his family, he is kindhearted and sensible.
He proves time and time again on how mature and responsible he is.
He is wise beyond his years for the most part, as he helps others out their problems by giving them great life advice.
Character development: While this is understandable and fairly justified, considering the fact that none of his family members respects him, he wished that he will never see his family again for the rest of his life. After being left behind, Kevin enjoys his freedom being alone, only to realize how lonely it felt to him and to acknowledge that he didn't appreciate his family.
He has his funny moments, especially at the start of the original Home Alone.
He is creative, as he develops elaborate traps to defeat Harry and Marv on his very own, which is very impressive and talented.
Macaulay Culkin did an excellent performance in portraying his character in both films.
Especially where his scream is comedic and memorable.
While still a likable and kindhearted kid, he can be rather mischievous and rebellious.
Given that he is still a kid and despite his talents, Kevin can lack some common sense in both films like kids usually do.
Even if Kevin is still the protagonist, some of his traps against Harry and Marv in Home Alone 2 can be over-the-top levels of cruelty and shows how painfully lucky he can be (ex: throwing four bricks at Marv). Where the aforementioned antagonists were utterly ineffectual.
Sadly, while remaining a likable character in Home Alone: Taking Back the House, he became a punching bag who would get tormented horribly by Buzz and Megan, while being treated as a butt-monkey by his father and Natalie. Not only that, but he also loses his personality in that film, going from a mischievous, but likable character, to a bland character that doesn't live up to the spirit of his original character in the first two films.
Kevin returns in Home Alone: Taking Back the House, and is portrayed by Mike Weinberg.