I think the characters overall can be divided into two major categories:
- Planned, full fledged characters and the ones to agree with Sakurai's criteria
- Clones, added at the last minute in development
To try to understand and make a pattern out of Sakurai's mind is obviously impossible. Everyone has their own way of thinking that only said person can understand, no matter how well they try to explain to other. Sakurai is no different in that regard.
This said, I have to very much agree with @
pupNapoleon
. Sakurai is, in a way, an artist. He's a game designer and a player at the same time, so it's obvious he has the passion for his job.
He tries to balance between a wide array of factors. Not all characters get in the game through the same means:
- Characters like Mario, Luigi, Pikachu and Link are very iconic to Nintendo, so a game about Nintendo's biggest stars will obviously feature them.
- There are characters that are chosen to bring back old classics like Duck Hunt or Mr. Game & Watch. Smash is a way of bringing those characters back into the spotlight that otherwise would be forgotten. When you also have modern characters, the game gains the unique charm of uniting many generations of players in one game, which I think Sakurai aims for, especially considering how the All-Star mode is organized.
- Sometimes the character simply inspires Sakurai to implement some creative ideas. Rosalina, Bowser Jr. or Greninja are good examples of this. Rosalina and her relationship with the Lumas paved way for a dual fighter, both fighting side by side. Bowser Jr.'s Clown Car was expanded with new contraptions and crazy weapons while taking cues from the original games. Little Mac was designed with boxing rules in mind, thus not adhering to the other characters' zaniness.
- Sakurai wants to give respect to a character. If he believes he can't properly implement the character, he will pass. I think Ridley was an example of this. Same for the Ice Climbers being cut.
- I believe Sakurai looks at popular characters first when deciding a roster and see which characters spark his creative interest. Popularity helps a character being in (to differing degrees), but is no way a guarantee.
As for the clones, we have two distinct cases:
Melee clones:
- They were added purposely to expand the roster, but Sakurai still chose which would bring the most uniqueness within the constraints as well as popular choices.
- Pichu had the self-damage mechanic, inspired by the fact he can't control his own powers due to young age.
- Sakurai considers a younger version of Link important, hence Young Link. Toon Link in Brawl and SSB4 is pretty much a successor character in this regard.
- Dr. Mario was made slower and bulkier as inspired by how a lab coat is less practical in an actual fight, but he knows anatomy to hit with precision, hence the added strength. Dr. Mario is an important mark in Nintendo's history, as it was an iconic puzzle game.
- Ganondorf was made a Falcon clone thanks to body similarity. Even with this constraint, the character is fairly well portrayed, by having brutal strength and powerful attacks backed by magic power, both essential characteristics of Ganondorf's character.
- Roy was added thanks to the inherent uniqueness of a flame sword.
SSB4 clones:
- Originally meant as aesthetic changes that evolved differently as a result of development's dynamic nature. In any large scale project, the initial plan will rarely be preserved to the end. This can be a good and a bad thing, as ideas are scrapped, but likewise, other ideas are brought instead. The clones here are a case of the latter.
- Like the Melee clones, they have an inherent uniqueness that sets them apart from their counterparts.
- Lucina was born out of the idea of making a newcomer friendly version of another character. Sakurai aims the game at all sorts of players, so he thought he could work an harder to master character like Marth and make an easier version of him. In a way, this parallels the Fire Emblem fans, with the older character appealing to older, more experienced players, likewise, newer, less experienced fans have a choice with an easier to use character that they're familiar with at the same time. Perhaps, that's why Lucina was chosen to be the easier character.
- Dr. Mario is once again back because he was different in Melee, so they naturally had the idea of keeping the status quo. And with Mario being changed in Brawl thanks to FLUDD, it was also an opportunity of bringing an old moveset back to the series.
- Dark Pit's separation stems from having a few different weapons as Pit that function differently, so he has a bit of such unique flair. In a way, he's similar to Roy. They stand out by possessing different weapons, inspiring different characteristics in their moves. Roy wields a flame sword and Dark Pit has an electric Arm, as well as the sniper-like Dark Pit Staff instead of the flashy Three Sacred Treasures.
Lastly, there will always be bias. Sakurai is human and, like everyone, has differing opinions on how the characters should be portrayed. If you were in charge of the game, wouldn't you put something to satisfy your own desires? Pretty sure you would, as you would have your own vision for the game. That itself is, in a way, bias. In creativity, it's difficult to tell right and wrong, and the creator adds their own charm to their own works. This is certainly not a bad thing.