I feel the same way. I remember the ballot asking for reasons why we support whatever character we voted for. Unfortunately, I don't think the shipment numbers from Chris' thread on neogaf were posted before that, and I can't remember at all what I had written on there.
But the first Golden Sun nearly sold two million copies on the GBA. A very young audience made up the GBA's demographics, if I'm correct. This is a series that sold very well, helped drive momentum for the Game Boy Advance hardware, AND created a young new fan-base for a brand new IP.
Think about it this way. Between the release of Golden Sun 1, and Golden Sun: Dark Dawn, Fire Emblem had five world-wide releases in between them. None of those FE games sold as well as Golden Sun: The Lost Age, much less, the original Golden Sun. Xenoblade just got its first million seller with XB 2, a third entry in this series, including X.
Golden Sun surpassed these games on a much smaller budget and had a young fan-base whom today have strong nostalgia for the games.
Yeah, Golden Sun Dark Dawn probably bombed at retail. You know what else bombed though? Fire Emblem Shadow Dragon. But that didn't stop that series from getting it's Awakening.
Bayonetta is getting three games now despite less than mediocre sales. Star Fox is having a rough time right now too, but the support is clearly there from Nintendo.
The point from me is that it is very disheartening to know Golden Sun had proven itself already. The series is still very unique among the sea of Role-Playing games that have released since, and yet Camelot and Nintendo never felt any need to recognize this series' accomplishments or keep the momentum it once had going.
In front of all this information, plus the suspect that Isaac did extremely well on the ballot (runner up to K. Rool?), Sakurai would have had to notice us, but then decided that either Golden Sun has no future entries coming, thus irrelevent and not considerable, he couldn't envision an Isaac move-set amongst the cast, or he has a bias himself that doesn't prioritize Isaac unless a new Golden Sun were to come out and become too big a massive mainstream hit to ignore.
As a fan, it's so disappointing because I feel we have a very strong argument for our character.
I mean, look at this:
This is Isaac in a nutshell (and then some). Here he is, 'dancing.' Who could look at this and not think this would be very unique and interesting amongst the Smash cast? If Sakurai needed a stronger visual guide to see Isaac 'dancing' in his head, here it is. It helps that Avatar: The Last Airbender had become a big hit in North America a couple years after Golden Sun was released.
Our character enjoyed stronger sales than some characters already on the roster. Our character is old enough to have nostalgia with once young players that played his popular game many years ago. Our character could grow to be popular AMONG SMASH FANS, thanks to the unique abilities he could bring to the roster. He could be an exciting addition to non-Golden Sun fans. His game has amazing music tracks to dig from. And more!
I believe we have a strong case for our character, and strong numbers requesting his addition. It's very disappointing to think Sakurai couldn't quite see Isaac's appeal the way we do. Other people on other boards don't quite get the appeal, but there has long been this feeling that, once Isaac got in, they'd come around once the saw what the character could do.
Anyway, we'll see what happens. Still hoping for the best, of course.