the hogwarts houses aren't ambition, brave, smart, and kind?
slytherin is ambition, self preservation and knowing your own worth. it's cunning and it's knowing how to get what you want or need. nowhere does it ever say evil, that was joanne kathleen rowling herself who said that
gryffindor is chivalry, bravery, it's the reckless care for the majority. martyrdom and thinking yourself the hero, wanting to be the hero, forgetting that self preservation is important too. in itself, gryffindor can be kindness, but it can also be twisted. because chivalry can mean traditional, and we all know that some of the most 'traditional' characters in the original books were purebloods
ravenclaw is wit, actually. it's not smart. i'd even bet that they have the worst grades out of the whole school, on a general level. it's curiosity and a love of learning, it's wanting to fill your mind and pursue the things that catch your interest. they were never the smart house. people just forgot that wit and smart are different words. wit, meaning something a lot similar to slytherin's cunning, if not similes.
hufflepuff is hardworking and loyal, according to the books. because hufflepuff is where kids go when you can't put them into a binary. it's not kind. there are people who could have been in slytherin there, people who could have stuck themselves in any house but were chosen for hufflepuff because they could have gone to any house.
and god, don't even get me started on how you can't call kids evil. you know how many young children are actually evil? the ones born or made socio or psychopathic. if my little sister was sorted into slytherin, that doesn't make her more likely to be evil. she's just a brat, unrelated.
ambition does not equal a tendency to evil. your upbringing and your own fucking choices do