Chief, you still forget that the makerss of smash brothers are japanese, and therefore will cater to the japanese fans more than international areas. Or did you forget that the poll was only in Japan.
As much as I'd like to see Lyn, Hector or Ephraim in the game, in Japan they are overshadowed by the favourites of the Japanese, namely Marth, Sigurd and recently Ike. Even if there are 4 FE characters in Brawl, the chances of Sakurai adding a character solely to please international fans is very unlikely, and probably just settle with Ike. Sakurai did say that he'd refrain from adding Japanese only characters though, but he still may add Sigurd due to his immense popularity (though I don't think he's incredibly likely), and might pull characters from PoR and GoD. Though I won't say there is no chance we will see other FE characters that have yet to appear outside Japan.
However, simply arguing that Ike shouldn't be in because he uses a sword is pointless. Most main characters in any fantasy setting use swords, so it's unavoidable that brawl will get more swordsmen. However, the smash team are very capable, and Ike already has qualities to set him apart from the other swordsman in smash (Link, Meta-Knight, Pit being confirmed, with Marth having a very good chance of returning). If it's simply an aesthetical issue, then that's simply opinion, probably one that Sakurai doesn't agree with. Fact is, if Marth and Ike play differently enouh, then most fans would be happy, regrdless that they both have blue hair.
As for Sigurd, I'm not too sure. He seems incredibly popular in Japan, and anyone outside Japan who's played his game see to like him too. However, if he does get added, it'll probably be as a swordsman. He does use a spear, but most art I've seen of him as him wielding a sword, plus I think his best weapon was a sword, and so far all Lords have had their ultimate weapon. And if we are to believe the rumours that he was going to be added in melee as a Marth clone, then it seems that Sakurai intended on giving him a sword based moveset. Still, he's the most likely Japan only FE character, and still has a fairly good chance of getting in (though only after Marth and Ike)