Okay, I feel like most of the reviews I've read didn't give this show the credit it deserves.
First of all, it seems appropriate enough for a kid at any age, but perhaps kids who are above 10 are more likely to understand and appreciate the witty lines and slightly dark themes. Sure, the spoiled kids get punished, but they're nothing too gruesome.
Also, I don't understand what people dislike about how Willy Wonka was portrayed. Wonka's weirdness and slight creepiness perfectly suited his character, and it's personally what I think gave him his mysterious-legendary-factory-owner vibe, which is totally awesome.
The only disappointing thing in the movie is that Charlie wasn't actually a well-developed character. He's a good role model, but he isn't all that lovable. Still, in the end, he got the message through: that family is something precious and irreplaceable.