One of the themes of my Youtube comic is the return of V'Ger's absorbed victims, including Decker and Ilia. You can call on all sorts of themes by ripping off capital from the cylons, Solaris, clone stories etc.
Ending the first-ever Trek movie with the destruction of Earth would have been a bold move, that much is sure. But probably a smart and popular one, too - after all, the movie had already bet on the audience liking the new Kirk, an incompetent and selfish asshole who fights the graying of his hair through arrogance, favoritism and unsound tactical decisions. Whoever said that protagonists had to be heroic or likeable? Whoever said they have to win? Well, Whoever was wrong: utter defeat is a great springboard for sequels! The more carnage, the more triuphing and/or escaping villains, the more desperation loaded into the post-cliffhanger spashdown, the better the hook for the audience to come and see how the next movie will up the ante. Timo Saloniemi
It would be up to Kirk and his crew (but mostly Kirk, of course) to repopulate the species. Perhaps Bones could GMO the women with some tribble genes to speed up the process.
I think that V'Ger's goal was not to destroy earth. It was to remove the carbon unit infestation because it believed that the carbon units interfered with The Creator. So, most likely, the plasma devices were geared toward digitizing organic units to data patterns. My guess is, to avoid pissing off the creator, V'Ger's weaponry wouldn't have destroyed Earth nor the machinery. My guess is tha V'Ger would have digitized Earth's life forms, and then still not have contact with The Creator, and it would need to reevaluate its mission. This in itself might have forced V'Ger to "evolve" in a way, because it would need to completely start at square one in terms of its purpose. Who knows? It's definitely an interesting "alternate universe" thought. Kind of like the Borg destroying the Federation in "Parallels" on TNG.
If there's no Earth, then the Federation might collapse. So the Sphere Builders are unimpeded to successfully invade the galaxy in the 26th century.
Obviously the seat of the Federation moves somewhere else, but maybe it'd survive Earth's destruction. I mean, humanity itself would survive. Lot of humans on Starfleet ships and colonies nowhere near Earth by that time period.
If V'Ger destroyed Earth, Data's severed head buried in San Francisco would also be destroyed, creating a paradox that would destroy the universe. Nice going, Data.
Then we wouldn't have had the movie with the whales...or the one with God in it...umm, that's not so bad.. RAMA
The Trek BBS forum would be a lot smaller with a whole lot less topics. What would we be left to talk about except for TOS and TMP? And I suppose the what ifs, like "What if V'Ger hadn't destroyed Earth but instead had a 3some with Decker and Ilia?"
The Decker Unit definitely interfaced with them both. At the same time. I'm sure I didn't imagine that.
I always loved the Babylon 5 episode where a couple of holographic characters figured they didn't exist, but had to stop a few terrorists anyway as their progenitors would. Without even being digitized. Spock can do more than that.
I know! In sequels the Enterprise would have led a rag-tag fugitive fleet...a shining planet, known as... er...
Which in turn would have led to the sequel Star Trek II: The Wrath of a Diet Based on Quadrotriticale