During the last rehab, they removed a scene of Triton (in laser form) telling Sabastain to look out for Ariel. In that scene's place now is a scene of Ariel arguing with her father.
As far as the length of the show, it's on the short side so they can do it many different times in one day. Because of the size of the theater, if the show was as long as Beauty and the Beast or Festival of the Lion King, they would not be able to get enough people through the show every day. There was a rumor that they were trying to add "Kiss the Girl" into the show during the last rehab but that didn't happen.