Ahaha, Ambipom seems more like a clown than something that's capable of being cute. That...permanent maniacal look on its face and its abnormally large head says it all. ¬_0
I...have not seen that movie! I lost track of the anime and movies long ago, but I'm slowly getting back into the anime after rewatching the old episodes.
Annnd yeah, it seems like Rhyperior's design seemed totally random, I don't know where they got the colours from...maybe they thought the colours would add to its "supreme" look. *shrug*