It does get a bit more crowded..but it is not unmanageable.
Usually gets pretty crowded at the Hub (Walt/Mickey Statue) around Noonish when they take their group picture.
As for the type of crowd, there is nothing to fear from them. I have found them to be one of the most respectful and considerate group I have ever run across in a Disney Park.
If you want scary go during Brazilian Tourist season.
Ummmm!
When is that??????????