Definitely. This act has major consequences for the character and the plot development in The Boys comic. It adds a lot of drama and complexity to the story.
In general, the Anonymous Noise anime is comparable to the manga. Some minor details might be different, but the core elements and themes remain intact. There are also visual and audio enhancements in the anime that add to the experience.
It's not a definite yes. The noise of the waves at night can be affected by many things. For instance, the type of coastline and the depth of the water nearby can influence how loud and persistent the sound is.
Hiccup in the fanfiction typically trains by forming strong bonds with the dragons first. He shows them kindness and respect, and then gradually introduces training exercises that are fun and challenging for both him and the dragons.
It depends on the plot and characters you have in mind. You could consider what would be the most exciting or meaningful decision for the story to take.