For: all plans
More transitions. On your movie's page, open the transition list. Under More you'll find Circle close, Clock wipe, Push left, Push right, Blur, Pixelate, Circles, Interlock and Page peel.
Music fades. Next to your music, pick a Fade in and a Fade out: None, 1 s, 2 s, 3 s or 5 s. The music fades in at the start or out at the end.
Voice volume. In a scene, set Voice volume to Quieter, Normal, Louder or Loudest. It changes only that scene's voice.
You hear the fades and the volume in the rendered video.