These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
The "I Will Survive" scene has Nigel playing along and rubbing his nipples. He's played by Rhys Ifans, who would later appear in Little Nicky as Adrian, who's Squicked out when someone does just that before him.
Growing the Beard: The first season was just passable, focusing on the gimmick with formulaic episodes. (The kids are displeased, someone is replaced, things are better, then they learn why the original was better and fix it.) However, by season 2, the gimmick was used in creative ways and the plots focused more on the characters themselves.
The Two Shorts format was also mostly abandoned - allowing the opportunity to tell more developed stories.