Real would mean you're a unit during REAL gameplay and not a tutorial.
We get it, she shows her face a lot. She's still not a lord or a good selling point for Smash.
Having several minor roles doesn't necessarily make one major role. Story wise, gameplay wise, and in terms of being well known she is a minor character at least compared to our heroes and main characters, I still say Sakurai is interested in representing the heroes and main characters of Fire Emblem and the characters that would sell both Smash and Fire Emblem. I believe he is also interested in the most desired characters which are Roy & Chrom. I acknowledge your points, but I still don't think this is enough to get her in over our main heroes. You can make points, but we don't have to agree that they are good ones. Anna has always had this role, yet I haven't seen her considered for Super Smash Bros. I don't think this small promotion she got in Awakening really helps her as much as one might think. I don't think THIS is the thing that instantly would sway Sakurai's opinion on Anna.
I'll say it again, I think main heroes/lords are better choices, more deserving, and would both sell games as well as please fans more than Anna would.
Then you are patently wrong, she
is used in 'REAL' gameplay in Awakening, both as the character you can control of the Trickster class (just like Chrom and the other folks), and as a Merchant NPC when there's a Risen spawned on a Special Merchant tile (there's far more than one Anna, and the Anna character in Smash would be like the Yoshi as a representative).
In the Fire Emblem fandom (Serenes Forest, Japan, the FE folks here), Anna is generally recognized for her mascothood, and she is quite a charming character, I guarantee that she has that element of Sakurai's criteria of attracting people to Smash, and to future Fire Emblem titles, it's a non-issue. People will identify more often in the future with a mascot than a Lord from a previous game if the lord's personality is incredibly dull, and that Chrom's is remarkably so. I say this as a lover of literature, however insignificant my word is.
As for the popularity claim, I'll grant that she's not particularly popular, but if I'm any judge of an attractive character, I'd say she's easy to warm up to, but then again this is not exactly the most important of Sakurai's criteria out of the four, especially considering his later interview with Polygon of what is important in a character, and the fact that he has chosen characters out of the blue. Another non-issue.
Story impact in games of a series often correlates to sales for Smash games, but the relationship is not causal at all, rather, it is the characters that sell Smash, and often they generate interest through story, but the interest they generate is just as much about their personality and traits, and I can guarantee that anyone who gains this through other methods, such as Anna, is just as well off as one who gains it through the traditional methods, such as Chrom, and in this respect I say Anna can stand up to the others, especially with her rich history and, heh, at least I think, interesting personality and traits. Heck, look at now, the favorability Anna has shown recently is a sign she's gaining interest in the fans, the fact that we're here and have some weight is enough.
Where gameplay is concerned, a unit or character does not make the gameplay at all, it's the mechanics which are the underlying force of gameplay, and Anna has the lore excuse to use to represent whatever mechanic from Fire Emblem Sakurai may want.
And for the pattern and precedent set forth by the previous games, the fact that we have a small data set without a serious contender that's not a Lord is the only reason it's stayed Lord exclusive, not because Sakurai and IS chose Lords, because that they have, but that simple fact does nothing to assure the future.
We may predict Sakurai's movement, but I say your estimation of Sakurai and IS is not so accurate, but that is mostly in the realm of obscurity, and on this point I can say I respect your opinion.
Time will ultimately tell, and if Anna does not tango with Lords this time, she will next time, as her importance can only grow as her roles amount.