This leads to this scene with her romantic "rivals", where she tells them to stop with the nonsense because Ranma is spending Christmas with her. That plan was already decided, but the way she says it makes it impactful because she had never been so openly honest with her feelings so far.

It also helps that the episode's animation is very loose and fun as you'd expect from an episode supervised by Atsuko Nakajima, the character designer! I also want to point out that at this point the designs have changed considerably compared to the beginning. This keeps the series refreshing!