It was you who scouted various Japanese boards to see what characters they like, right? If so, do you also happen to know how the Japanese think of the Golden Sun series?
During pre-Brawl, Isaac was a pretty frequent request in Japan. He was certainly less common than Olimar, but in terms of other potential new series newcomers. He was definitely ahead of the rest of the pack.
The tragic thing is that the passage of time has not been nice to the Golden Sun series (or Isaac) in Japan. The series (and Isaac) have fallen down the memory hole there. Requests for Isaac (or Matthew) were very rare from checks I have done in recent years.
Its worth nothing as well Dark Dawn was absolutely DISDAINED among the Japanese player base, and game bombed very badly in Japan (sold less than 100K). The dismal performance of the latest game in Japan as well as the very strong negative reception by those that did play it makes the outlook for a fourth game look dismal. Even the guys behind the series in recent interviews seem very reluctant to want to do another installment.
Also, my apology and elaboration of my views got buried on the bottom of the previous page, so I will re-post it:
Also, I am sorry if my personal opinions on Mother (and future potential newcomers for it) offended any Mother fans. I did not mean to be obnoxious or domineering towards anyone I was responding. Simply liking a character is a valid reason to support a character (for example, I probably the only person in this thread that has brought up Pico, because I am probably the only one that has likes him, or head of him, F-Zero is very niche unfortunately). If you want the Masked Man in, its cool, its your vote. As with people disagreeing about Pichu or BlackShadow/Ganondorf, people have different parameters or belief systems that cause what they believe to be a good or bad addition.
I feel passionately about this (potential newcomers) in general because I would like to see characters that feel the same way as Sakurai's own newcomer additions and fit the meaning of Smash Bros. (as opposed to the characters I personally like the most or think would be the easiest ones to go with) Even characters like ROB and Wii Fit Trainer have incredible importance to Nintendo (ROB being the trojan horse that saved the North American game industry and a symbol of Nintendo's toy-designer legacy, and Wii Fit Trainer representing a franchise with multiple installments that have sold well over 15 million copies and one of the icons of Nintendo's Wii revolution).
That is why although I personally feel lukewarm about Lyn, I gave her one of my votes. Although she may not be significant to the Japanese side of things, she is to Western fans. I also personally like characters like Toad, Paper Mario, Little Mac, Pico, and K. Rool far more than any Advance Wars character, yet I included an Advance Wars character in my five votes because its a long-running series that is both well-loved and lacking any major content in Smash Bros. and likely won't in Smash 4. For a character fanbase its bad enough their character of inclusion is not included, but for an entire universe to be excluded, in such a gathering of all Nintendo's franchises like Smash Bros.?, I think that is worse, especially at this point. The same goes for Golden Sun (personally, have never played a Golden Sun game and have no exposure to Isaac as a character) except on an even greater scale than Advance Wars. Golden Sun's popularity and accolades rivals that of many series that do have playable characters already in Smash Bros. Again, its a series that will probably be overlooked again in Smash 4 (though not as likely as Advance Wars).
Of my votes, only Ridley and Dixie Kong I like personally as characters However, even there I felt they had a reason to be in Smash Bros. Ridley is basically the most popular, important, and recognizable Metroid character next to Samus, and is arguably the most important Nintendo character from a veteran franchise not yet playable (truly among the few characters that could be labelled a Nintendo All-Star not yet playable).
As for Dixie Kong, both her and K. Rool have impressive credentials. The DKC trilogy is among the most loved of games on the SNES, and have stood the test of time. One has been the main or co-starring protagonist in two out of three of the DKC game, while the latter was the antagonist in all of Rare's DK games (albeit with thinly veiled disguises in subsequent appearances). Between the two, I felt that the hand to go more towards Dixie not just she would be the easier between the two to develop (I personally regard Dixie and K. Rool as equally important to the DK series at this point) but also she has the distinction of being among the few characters that was planned to be in Brawl at some point before being scrapped (Forbidden 7). Mewtwo, Roy, and Dr. Mario, all Forbidden 7 characters, have been restored to playable status in Project M. Of the remaining Forbidden 7, we have Toon Zelda (altergo clones aside from Toon Link usually have mixed or negative receptions), Toon Sheik (an original character that does not qualify since she technically made no appearance in Brawl), pra_mai (there is all sorts of debates about what this is, but I think its Plusle & Minun, but others will strongly disagree), and of course Dixie Kong. Of all these four planned newcomers, Dixie Kong is easily the most popular, important, and iconic to her respective series. It would be nice to see the team restore one of Sakurai's planned extra Brawl newcomers (Mewtwo, Roy, and Doc are all veterans) and to add in what is arguably Nintendo's most important heroine not yet playable in the Smash Bros. series.
Although there is plenty of characters I like and love over Lyn, Isaac, and an Advance Wars newcomer, I thought about what characters:
1. Could be very well-received
2. Development ease (though Isaac and Ridley are legitimately difficult ones)
3. Importance to Nintendo as a whole.
Lyn might be the flimsiest on the last point, though, looking at a Western lens in general, we certainly care more about Metroid, Golden Sun, and Advance Wars far more than the Japanese fanbase does, and FE7 is generally still the most popular FE in the West (FE13 might rival it now though, however, lets see how that game will survive the passage of time).
I generally want to see a set of newcomers that would be something Sakurai would pick if he had more Western inclinations (hence looking at Metroid, DK, Golden Sun, Advance Wars), as opposed to characters I just really happen to like.