With the ending that the series had, it was very disappointing for me. In response. The following is a What-if arc for the ending of the series.
The Major antagonist should have been a human. A human with an immense hatred toward gems and was formed a grassroots movement & A Red Ribbon - Esque faction dedicated to establishing a sovereign earth policy and the complete deportation of Gems off of Earth. Of course. The human antagonist would call himself The "Commandant" of the faction. To expand more on this storyline, what if he somehow achieved a rock with Gem powers and gave his army homeworld weaponry. To top it all off, The Commandant gets enough support from earth's governments to build a laser to blow up homeworld in retaliation for all Gem Activities (Kindergarten, Spinel's Injector Incident, Lapis's Ocean Tantrum, etc.)
Thus, the final episodes should have been The Crystal Gems versus the Gem weapon equipped anthropocentric paramilitary and Steven brawling with the Commandant, and destroy the laser before it destroys homeworld.
This battle would’ve escalated to the point of the Diamonds getting involved, causing the Commandant to OD on the gem powers and mutate himself, overpowering the gems and the diamonds.
A traumatizing event during the battle such as Greg or Connie getting hurt would’ve triggered a rageful transformation within Steven, causing him to go nuclear on the mutated Commandant. This starts off an epic fight sequence a la Incredible Hulk / Every Anime Ever, turning Beach City into an all-out war zone.
Several things could’ve happened from this point
Connie is healed but is turned into a gem and attempted to calm him down
Pink Diamond is revived within Steven and turns back into her original form to fight the Commandant.
Both Steven and The Commandant become corrupted and have a kaiju battle in the ocean
Either way, Steven, Greg, The Gems and The Diamonds should’ve at least seen Pink Diamond one more time, just to have closure. Of course, it ends with some sort of victory and some sort of treaty is made between gems and Humanity.
If the show ended in this fashion, it would’ve been the perfect sendoff.
