Star Trek IV: The Voyage Home had a deeper ending
When Star Trek IV: The Voyage Home was still in the writing process, Harve Bennett worked with Leonard Nimoy to come up with an idea that involved Birds of Prey, Klingons, and the Super Bowl. Needless to say, Paramount didn’t like the idea and wanted something different. According to WarpedFactor, Nicholas Meyer, who was the writer and director of The Wrath of Khan came onboard to help with a rewrite. He and Bennett worked together for the next twelve days. Meyer handled the portion of the movie where the crew went back to the 20th century while Bennett wrote the beginning and ending of the movie.
In the final draft of the movie, Gillian Taylor, who was the assistant director of the Cetacean Institute where the humpback whales George and Gracie were being held, jumps into Admiral Kirk’s arms at the last minute to beam aboard the Klingon Bird of Prey the crew used to go back in time. Her actions took her to the 24th century with Kirk and the crew. But that wasn’t Harve Bennett’s original plan for her.
Gillian Taylor had another purpose in Star Trek IV: The Voyage Home
In the first draft of the movie, Gillian Taylor doesn’t join Admiral Kirk on the trip around the sun to the 24th century. Instead, she chose to remain in 1986 on Earth where she can protect the humpback whales and make sure they survive for the future. Nothing was mentioned about how this would have affected the timeline, but then, we have no idea if the Enterprise crew’s arrival in 1986 and subsequent capture of George and Gracie created a snafu, either. Nothing was ever mentioned so we just assume their actions didn’t change anything.
At any rate, Nicholas Meyer actually preferred the original ending because he felt it was right.
"“The end in the movie detracts from the importance of people in the present taking the responsibility for the ecology and preventing problems of the future by doing something today, rather than catering to the fantasy desires of being able to be transported in time to the near-utopian future.”"
But part of the fun of the ending of The Voyage Home was imagining being transported from a life with little technology to a world of endless technology and possibilities. Who wouldn’t want to take a journey forward to a utopian society? And honestly, when I watch the movie (which I’ve done more times than I’ll ever admit), I think more about how cool it would be to start life anew three-hundred years in the future. So, personally, I like the ending and wouldn’t change a thing about it.