I've been saying all along that Chrom's chances have been overstated. Not that he's a terrible choice or a highly unlikely one, but I never felt as he was among the most likely characters, even after E3 2013.
Let's be honest here, Rosalina was not a popular choice around here. For many reason, I would have dismissed her, even after her playable appearance in Super Mario 3D World (even though I liked the character, just didn't see her as "deserving"). Rosalina is positively received because of how well her move set is being done and how enjoyable her play style is. I guarantee you that if she had been a semi-clone, her inclusion would be despised.
We're at the point where uniqueness is necessary for most characters to get in and this extends to Chrom as well. Chrom getting in as as semi-clone, especially as the expense of Ike, would be a very bad move on Sakurai's part. If this happens, he will be one of the worst received characters in Smash and stick out like a sore thumb (and in a bad way). With Sakurai's extensive focus on uniqueness this game, I believe Sakurai is aware of the similarities Chrom possess with Marth and Ike. Luckily, Chrom is able to utilize weapons from different classes that can make him unique and this can make him an enjoyable addition. However, I feel as if this is not the case, either Chrom will end up being one of the worst received character in Smash or he will not be in.
I think it's unfortunate that not much has been done with F-Zero, cause the cast of characters is great. I think Goroh is obvious, but if we were just talking about fun characters, I would love to see more of Pico, Mighty Gazelle, and Silver Neelsen.
What would be awesome is if Samurai Goroh got in and pulled a Captain Falcon in regards to uniqueness. Can't be impossible to do, plus it would be nice to see a second F-zero character.
ICaptain Falcon is all we'll get, and all we'll need until hell freezes over and we get a new F-Zero.
You never know. There was no good reason to expect Rosalina outside of uniqueness and she got in.