YABU - I think the casting is great.
Danial Radcliffe is right for Harry, except for the green eyes. The hair is right and he even has the same scar as in the book! (OK, the scare comment was a joke, I hope you got that).
Snape looks perfect for the role IYAM. Luipin is fine, didn't get much image of him. The weaselies all look perfect to me.
Emma Watson, yes she did grow up to be very pretty. As did Hermione. That was partly the point. If you read it properly, she was very pretty. The reason why the boys didn't find her very attractive (well, some did) was because she barely brushed her bushy hair and she didn't wear make-up because she spent her time studying not trying to look pretty. She also walked with a slight hunch from carrying a huge pile of books.
I'm sorry if he ever reads this, but the guy who plays Ron is a bit ugly. But that is Ron. Ron was supposed to be quite ugly. But Hermione is not that shallow that she cares about looks much. That is the other point. She likes Ron's other qualities.
Oh, and yes, Luna Lovegood is great for the part. I think Harry should have ended up with her, not Ginny realistically. Mainly because of the hero complex Ginny has for Harry after the Chamber of sectrets would make a long term relationship fail. Luna, on the otherhand, is always their for Harry, and always understands him. Or perhaps it's just me who thinks that's more important.