In all honesty, I haven't set them up side by side.. but is there even enough information to suggest she could be Han and Leia's?
These are the chief reasons why I think people speculate a Luke connection (more or less in order of importance):
- Rey is very strong with the Force, which matches what we know about the Skywalker line. (It's easiest to match her Force abilities to a known quantity like Luke.)
- Rey appears to have literally inherited the lightsaber from Luke, based on what we hear from Maz about how the lightsaber has been passed down ("This lightsaber was Luke's, and his father's before him, and now it calls to you!" specifically mentions Luke, so naturally the impulse response is to guess at a connection to Luke.)
- Rey's origins very tightly parallel Luke's origins (orphaned on a desert planet, forced to do menial labor to survive, leaves once the arrival of the Empire/First Order to capture a droid whose mission is to bring back a Jedi from exile draws her into the conflict against evil), which is often a sign of a direct (and often familial) connection as a storytelling convention
- Rey is also a great pilot, in line with what we know about Luke. (This is less of a strong connection, since pretty much everyone in the Star Wars universe isn't half-bad at flying ships anyway.)
But I think we can subvert all of those connections (by linking them back to Anakin and tracing her lineage through Leia instead).
- Rey's strength in the Force also mirrors Anakin's, and we know Leia is also capable of passing down Force powers. (She's also yet another known quantity in the equation.)
- The lightsaber is also ultimately handed down from Anakin, even if she's Leia's kid. (Luke will ultimately be the one to teach her, since he's the one who actually became a Jedi, and he's the one who "lost" it on Bespin, leading it to be left for her.)
- Rey's desert planet/menial worker origins also heavily mirror Anakin's, with the bonus that Anakin's actually known for his mechanic prowess in addition to his piloting skills (yet again, a known quantity) - something Luke isn't known for anyway.
- Rey's piloting skills likewise really come primarily from Anakin (another known quantity), regardless of whether she's Luke's offspring or Leia's.
Here's the kicker, though: if we look at Rey appearing to "inherit" the lightsaber in a generational fashion as a signal that she's tied to the Skywalker lineage (either Luke or Leia), shouldn't we also consider other imagery that evokes "inheritance"? And what do we see?
- Rey is given a blaster by Han. Yes, Finn is
also given a weapon by Han, but when Han gives the blaster to Rey, it's beneath a couple interesting conditions: the offer of a job serving on the Falcon, and the statement that "you have a lot to learn" - neither of which are offered to Finn. So while both characters receive blasters from Han,
only Rey does so in a context that relays a kind of fatherly tenderness and the willingness to take her under his wing. The film loops back to the special connection developing between Rey and Han later (during the Rey-Ren interrogation scene) and
specifically calls it out as the kind of father-daughter relationship that Rey never had.
- After Han dies, Rey appears to literally inherit both the Falcon - Han's most prized possession, which he refers to as his "home" - and Chewie - Han's lifelong partner.
The film doesn't belabor any kind of setup for why the Falcon and Chewie end up with Rey; it's taken for granted as the film moves along to the ending.
Rey also "inherits" a specific characteristic from Han that
isn't associated with Luke:
a deep reverence for and appreciation of the Falcon. The film draws several direct parallels between the way Rey feels about, understands, and treats the Falcon and the way Han does. These moments tie in with her mechanical prowess, too - the one thing we know isn't a characteristic she also shares with Luke.
What runs against this theory? The fact that Han and Leia don't directly demonstrate any recognition of her, for one. But that's just as problematic if she's Luke's child, as in that case she'd be their niece - she'd still be family, and the fact that they never acknowledge this would still be just as weird.
The film is careful to place any conversation between Han/Leia and other characters off-screen. In particular, there's the scene in Maz's tavern where Maz explicitly asks Han "Who's the girl?" before the scene cuts to Finn and Rey. Now, it's possible he simply doesn't know her and nothing of value was said, and so the whole conversation was just a red herring. But that this pattern was repeated with his first conversation with Leia about Rey - it also happened off-screen - gives the impression the filmmakers are intentionally being coy about what these two characters know about Rey, a pretty good signal there's a strong possibility there's something there to keep under wraps.
In the absence of any other evidence that would account for why Han and Leia wouldn't react to Rey like family (whether she's their niece, in line with the leading theory, or their daughter, in line with this other theory), and with both theories being effectively equal on that count, I think the film's deliberate avoidance of these conversations is meant to signal to us that the characters themselves know
something but are - for some reason - disposed to avoid revealing whatever that is to Rey (or her friend, Finn).
In any case, whether she's Luke's daughter or Han/Leia's, I think there are way too many coincidences surrounding the way the Falcon landed in Rey's lap on Jakku - Han conveniently didn't search for the Falcon in the region where she was left, where she was living alongside the junker (known to Han) who happened to also end up with his ship, and yet somehow he wound up finding the Falcon pretty incredibly quickly after they left orbit (and even said outright it wasn't a coincidence). So my hunch (it's weaker than the rest of the guesses I make, admittedly) is that Han knows something about who she is/why she was left there and isn't telling.
In the end, I don't know that either possibility is necessarily more or less likely. During my first viewing, I actually wouldn't have been shocked if the last line was Luke saying "I'm your father" to Rey. However, after repeat viewings, I don't think the film has closed the door on the possibility that she's Han and Leia's child, in spite of what many have suggested.
I'm also open to the not-Skywalker idea, since really its biggest support - that Rey's strong with the Force - comes from an assumption about Force powers that may prove to be untrue (and that Abrams's statement, shown a few posts back, actually undercuts). In the end, there's no reason to conclude that someone "strong with the Force" has to be a Skywalker; neither do we have to conclude that the will of the Force will link only Skywalkers to the evolving Skywalker story. But I'm also actually really fond of that (primarily spiritual) interpretation of the Force and I'm predisposed to think it's a good idea since it really reinforces the way I feel about the ending - that Rey's victory over Kylo is a victory of her belief and faith in the Force (the spiritual approach) over Kylo's raw mastery and brute power (the scientific approach).
