Maybe not the best thread for this but the news on Isaac having never been considered really irks me. The character (or the series) not being popular enough is entirely on Nintendo. It's the same story for Advance Wars, Custom Robo, and Golden Sun. A single 7/10 instalment in an otherwise fantastic series is enough for Nintendo to pretty much give up on them entirely.
Nintendo isn't the only party at fault here, though. Sakurai has to know that he has a huge amount of power when it comes to reviving a franchise to put in Smash. "Too many Fire Emblem characters" would not be something we'd even fathom if it weren't for Sakurai deciding on putting Marth and Roy in Melee. He brought the series back from the brink and introduced it to the West, and enough interest was generated that it's become one of Nintendo's flagship series. Kid Icarus as well was as dead as dead could be before Sakurai decided he liked Pit enough to completely reboot the series, and then added two new characters from it in the next Smash Bros. game.
It's frustrating because it could be popular if he wanted it to be. He could have made Golden Sun, Custom Robo, Chibi Robo, and Advanced Wars household names and created demand for sequels. That's a lot of power for someone to have.