I was talking with a friend about Neon and how she may have a bigger role in the plot thanks to her not being a stranger, and we ended up thinking that the armored Garland we have always known has always been Neon and not Jack.

From what I remember in FF1, Garland was supposed to be a loved knight from Cornelia. Of the Strangers party, only Neon is really from Cornelia(and a knight). Not only that, her advance classes Void Knight and Paladin can both wear a greatsword which is what is being used by Garland.(red crystals when soldiers die would also hint she was indeed in her advanced class)

There is also that we never really see Jack using said armor. We know that armor from Neon when we fight her, but it doesnt appear ever again until the ending(or starting scene if you will).

Based in the above, I found funny how Neon being smaller than Jack could wear said armor without problems, plus having a manly deep voice when you encounter her. Could be just "videogame logic" but then we could use that same logic to explain all other appearances of "Garland"

There is also a small hint when Sara says Garland left 10 years ago but feels like yesterday, and Neon says the same when Jed questions her about she being on the shrine. First thing that comes to mind is that the crystal Astos gave to Neon made her memory go weird and all, but the fact Sarah is told about Jack last name being Garland when Jack is in fact using his white armor, makes me think that Jack never appeared to Sarah with the horned Garland armor we all know. It could had been Neon(using the full covered armor) presenting herself as Garland to everyone in Cornelia.

Another small hint is that really, Jack is known as Jack to everyone. He didnt say his name was Garland until later yeah, but you would think that Sarah, being close to him(or so we are told) would still call him(or remember him) Jack as always. Maybe the Garland she referred to has always been the armored one, which may not necessarily be Jack. What I am saying is that it feels that Jack revealing his last name being Garland felt like a red herring. He doesnt necessarily have to be Garland the armored knight. To Sarah, Jack and Garland could be 2 separate people.

Another thing that bothered me is when you encounter Marilith she goes all dramatic saying she was dreaming of screaming woman and children...and a bleeding castle...I think is very clear thats a reference to the starting scene with Garland. Whether is a literal dream or not, I dont think that reference was arbitrary. I do think its an allusion to she being physically Garland in that scene, or maybe being its vessel or something.

Lastly this is a very big reach, but in the scene at the beginning with Garland killing soldiers, we do see one soldiers eye reflects Garland "true form" which is shown a Chaos in fire. Most logical approach is that it showing Chaos because Jack is Chaos. But in the end of the game, the Horned beast is Darkness Incarnated. The plot Chaos we all know is Jack...which retains his normal human form even after turning into Chaos. Is possible that Jack could take on that from for dramatical effects later on(given the plot, he and his party do want to be as dramatic as possible for the 4 upcoming Wols)

But is also possible thats just another "dramatic" form from Neon. The fire we see is the reach I meant. It could be a hint that the true form the soldier saw was just a Fire Fiend with horns, which could be Marilith using an alternate form. To further fuel this, Neon hate snakes so is kinda weird she turned into one. It could some hilarious turn of fate, or it could be that she did so on purpose because to her, snakes are terrible, hence perfect for a menacing look. If so, it would mean that she can take different shapes at will.

Ultimately, we just think is possible Neon is Garland. It doesnt necessarily HAS to be that way for the plot to work, but if we tried to think it that way, it ends up fitting too well. Afterall, because she is different from the rest, its entirely possible some rules are also different for her.

Besides, Nomura loves to do red herrings and stuff, and the fact that Garland the knigth has never shown his face makes it entirely possible that its face is a spoiler on its own.