Well since the topic was brought up while I wasn't around to discuss it I'm gonna pull a Diddy and bring back a dead topic to give my opinion on it, sorry guys.
I'm mostly addressing this to Chrono since he was the one with the most doubts.
Anyway, in regard to Lyn, I feel it would be best as to describe where I stand and why I support the character and why I think others do.
With me, it's simple, it goes back to high school. I had a good buddy back then who introduced me to Fire Emblem after he got Path of Radiance on Christmas. We both awed at the game and how badass the main character was (Ike), but also came to like a lot of the side characters, mostly Shinon in my case, but there were others such as Stefan and Soren. Since PoR, both me and him became huge junkies of the series and set out to play all the games we could in the series. So then we moved onto FE7.
Now, FE7 stood out from the GCN game in that the sprite animations were more dynamic and gave the games a very unique sense of flair. Especially with those critical hit animations. Now upon booting up the game, the MC at that point, Lyn, really didn't stand out from Ike in regard to personality, and overall coolness. That is, UNTIL she got a critical hit on someone, which was usually rather early in the game considering she was a Myrmidon-like class.
My reaction to first seeing her land a crit hit back then would best be described as such:
"Holy ****!! Lyn just owned that guy, he stood no ****ing chance!!" (this was 2006 mind you, don't forget we talked like that back then).
I think it's fair to say that the Myrmidons and Swordmasters in the GBA Fire Emblems have some of the best CritHit animations, alongside the lone Assassin Jaffar. The high speed movement and strong IMPACT of the attack really left an impression on my young and simple mind.
Since that point, I (and I'm sure many other players as well) were inclined to send Lyn out into battle just to see her land another critical hit, which usually ended up with a Maxed out Lyn well before her promotion.
Anyway, once Brawl was announced I remember talking with my friends and mentioning how cool it would be to have Ike and Lyn in Smash, and all of us agreed that Lyn would certainly be an cool character to have because of her high-speed swordplay. All of us were competitive Melee vets, but really we weren't looking at Roster Diversity, nor Series representation, nor advanced fighting game mechanics. We simply wanted a character that could fight like Lyn fights because we thought it would be fun to have a character like that.
So in short, I and other people support Lyn, simply because she's the only character we know that could lend that fighting style, arguments like "she could be a clone," or "so and so can also be unique" are fickle strawmen, because they don't capture the essence of why I truly support the character. In the long run, I could care less about roster diversity, or series representation or any of that other stuff. Ultimately my support for the character goes back to a young era and the memories I held with my good buddies from high-school and thinking how cool it would be to have a character that could play like that. We were young high-schoolers reading Manga like Bleach and Ruroni Kenshin/Samurai X both of which placed a huge emphasis on swordplay, and honestly no matter how much others try to argue, the fact remains that the only character that can give me that playstyle is Lyn.
I imagine that when people say "diversity" or "uniqueness" that they were also left by the same impression from Lyn and FE7 as I was. In that regard, the support for Lyn is as "pure" (for lack of a better word) as the support for Roy for example. The Roy fans mostly support him because they liked the character in Melee. And I think it's fair to mention that IS is certainly aware of the fanbase built around Lyn by those who enjoyed FE7 over in the west. That's why they've given her a spotlight over Eliwood and Hector, both of whom are argued to be better units by the hard-core fans, AND more important to the story. But as Horsetai had said, it's not about the importance to the series. Really, it's about how much people like the character. Does that turn Smash into a sort of popularity contest? Yeah, in a way...
Last bit, this is not to say that of course there aren't bandwagoners and waifufags that support Lyn. But really, when you look at it, EVERY character has that. For one, Roy has fangirls. But that aside, there are many people who have their top picks, but are still undecided on a couple and thus jump back an forth on what they choose to support. Hell, I can admit to this in regard to the Saki, Isaac, Shulk deal. I mostly support Saki, but I'm overall undecided, same with Toad and Paper Mario. So discrediting support for a character because it's a bandwagon is rather unfair. Support is support simple as that. It's like politics really.... blegh...
Anyway, this is not to say that I feel Lyn really has a solid shot this time around, nor that I feel she will get in. However, I still hold my opinion and my support. All in all, I've been able to show people what I like about Smash all in all through this character. I've been able to show how important gameplay is, as really, that's all I really look for in a videogame, and the coolness factor I had found from Lyn many years ago is what drove me further into competitive gaming.
Well, to those who were patient enough to put up with my rant. Godspeed. Hahahaha. I just wanted to get that out of the way is all and hopefully clear up some doubts and dissent.