Star Wars: The Last Jedi - 8 Parents J.J. Most Likely Wanted For Rey
2. Luke Skywalker
The most obvious choice is the one it's fair to say most people were betting on. Having Rey be the daughter of Luke would have been the easiest connection to make. Seeing as the prequel trilogy was about Anakin, the original trilogy was about Luke, having the sequel trilogy be about Luke's children almost seemed like a creative default.
The entire Resistance spends the entire film looking for the self-exiled Luke Skywalker, but Rey is the one who gets to go once they find him. His family lightsaber calls to her, she's a chosen one living on a desert planet, and she even gets her own speeder that is highly reminiscent of Luke's own from A New Hope.
Hindsight being 20/20, a great many if not all of these were just Abrams way of paying homage to A New Hope. He was linking Rey and Luke because they were both the hero of their own hero's journey, first and foremost. But Abrams certainly at least explored this option with Kasdan during the writing process.
Again, the novelization of the film and even the script itself offer a bit more insight into this possibility, as both have Luke seemingly recognizing Rey when she beckons to him on Ahch-To