People need to realize that it's not the number of games that's the problem.
With just two games, Sakurai already felt the series was deserving. However, his problem was that characters from the series don't fit Smash's violent nature.
I assure you, if anything in New Leaf pops up that adds any sort of violence, a character would be added in a heartbeat.
once again, I agree with GoldenYuiitusin.
Animal Crossing just doesn't fit with Smash Bros.
Brawl already represented the series very much, with a stage, an assist trophy as well as the Pitfall item.
taking a character from a life-simulating game and put it in a fighting game is just off.
besides, what are some of the few Assist Trophies that are useless? Mr. Resetti, who just rambles about and Nintendog, who just block the screen. what I mean with this is that characters from these series just don't have any fighting prowess.
to further prove my point, here's a list of fighting occasions of all characters already featured in the Smash Bros. series so far:
[COLLAPSE="Click to expand"]
Mario series & sub-series:
Mario - Platform games, he essentially beats up Goombas and Koopas time and time again. Also starred in RPGs, which, guess what, have battles.
Luigi - See Mario.
Peach - Playable character in Super Mario RPG, need I to say more? No? Good!
Bowser - Fights Mario and is a boss. 'Nuff said.
Dr. Mario - Well, duh, he's Mario in a doctor's outfit.
Donkey Kong - Mario's archrival before Bowser. Shows enough fighting in DKC and other of his games.
Diddy Kong - Also a character in DK games.
Yoshi - Fights alongside Mario. Also has his own series of platformers.
Wario - More or less the same reasons for all characters above. Is a boss in his debut, also stars in his own series.
As you can see, all Mario characters have their share of fighting, there are boss battles in the platform games, as well as RPGs, which involve fighting as well. So, it works in Smash.
The Legend of Zelda:
Link - He has a sword, bombs, a bow... what are these? Weapons? What use has a weapon? Ah, yes, fighting.
Zelda / Sheik - Uses magic and light arrows, also has her share of fighting, specially in the final battles against Ganon. Sheik also proves to be quite capable of putting a fight. Why? The Sheikah are portrayed as the protectors of the Royal Family, and if you want to protect anyone, you must know how to fight back enemies, right?
Ganondorf - He's a dark lord. What kind of dark lord-type character doesn't fight the hero in the end? Has a sword and uses magic, originally. He's more than capable of fighting.
Young Link / Toon Link - See Link.
Zelda's an adventure game with lots of fighting and bosses. Works for Smash as well.
Metroid:
Samus / Zero Suit Samus - Bounty hunter? Check. Kills Space Pirates? Check. Has a badass Power Suit with lots of weaponry? Check. Has an emergency pistol and good physical strength? Check. In order words, works perfectly.
Kirby:
Kirby - Possesses the ability to copy opponent's attacks. Do I need to develop on the subject?
Meta Knight - Has a sword. 'Nuff said.
King Dedede - Has a massive hammer. Is usually the final boss in the Kirby series.
All Kirby characters have fighting abilities and work fine for Smash.
Star Fox:
Fox - Even though the games are rail-shooters with space ships, it is implied that Fox might recieve some training in ground. In fact, later games also feature fighting on foot.
Falco - See Fox.
Wolf - See Fox.
Despite being in vehicles, the Star Fox characters also have their share of fighting.
Pokémon:
Pikachu - Come now, one of the main premises of this franchise is the fighting between the monsters themselves, and they have quite the array of moves.
Jigglypuff - See Pikachu.
Mewtwo - See Pikachu.
Pichu - See Pikachu.
Pokémon Trainer - See Pikachu.
Lucario - See Pikachu.
Fire Emblem:
Marth - Fire Emblem games are about war and Marth has a sword.
Roy - See Marth.
Ike - See Marth.
EarthBound:
Ness - RPG series, like Pokémon. Ness possesses PSI powers, which can be used to beat up whatever thing he meets.
Lucas - See Ness.
F-Zero:
Captain Falcon - Outside of the races, C. Falcon is a bounty hunter who hunts down criminals, likely requiring a beating too.
Game & Watch:
Mr. Game & Watch - Some G&W games involve fighting or violence, such as Vermin or Boxing. Lion involves avoiding lions to flee from the cage using chairs, implying that you hit them with chairs.
Ice Climber:
Ice Climbers - Climbing mountains for veggies, while beating up Topis and Polar Bears that stand in your way. Did I say they have hammers?
Kid Icarus:
Pit - Pit has a bow and beats up Underworld minions with it.
Pikmin:
Olimar - Uses the Pikmin to beat up wildlife that threatens him in his objective of repairing the ship. When alone, he's also capable of punching his foes.
R.O.B. series:
R.O.B. - Not even a character by himself, but putting a robot in a fight isn't too farfetched.
Third Party characters:
Snake - He's a soldier and is armed to the teeth. 'Nuff said.
Sonic - Possesses fighting abilities. Starred in two fighting games before.[/COLLAPSE]
If you read all of this, you now know what tells apart these characters and the Animal Crossing villager. They get involved in conflicts and fighting isn't out of their character.
What do you do in AC that compares to what these characters do?
There are no battles whatsoever, no boss fights, no conflict of any sort.
What makes you think that a happy-go-lucky villager who spends his time decorating his home and such activities suddenly appear in a Smash Bros. game beating up whoever gets in his way? That's the question, folks, not the quantity of games released or importance. It's the character himself, his characterization as portrayed in the source games themselves.
All characters in Smash are fighters already in their source material, while Animal Crossing doesn't contain one bit of violence or conflict. I think it's pretty obvious on why these characters are unfitting for Smash.