I'm bored so here's a tier list of how powerful smash 4 characters would be
if based on the games they come from. Feel free to disagree, comment or add to it. Many places are based on educated guesses.
S
Although Link beats Ganon in the end, the Trifore of power is by nature the most powerful of the three. Ganon rules over the massive monsters characters like Link and Samus fight. Palutena is a demigoddess. Although she gets rescued by pit and it's hard to tell how much she's BSing Pit about her powers in KI:U, she is still a goddess. She commands Pit and rules from heaven. She doesn't get a tier of her own though. Mewtwo is the most powerful psychic pokemon and often the strongest in the games he's featured. In the movie he's controlled an army of pokemon and conjured a huge storm with one hand. You could argue that fighters like Samus or Link could potentially beat S tiers but they are the 'bosses' the underdogs must rise to overcome.
A
I'm guessing Lucario is a step above the remaining pokemon, IDK. He could be a tier lower. The others are heroes who have proven countless times they stack up with the toughest. Link/TL has beaten monsters like Bongo Bongo, Majora, etc. Link can also wear a tunic that allows him to walk on lava. Samus fights monsters of the same caliber, survive in space and in lava. Sonic has defeated monsters like Perfect Chaos, Time Eater, and huge robots; these seem on par with Metroid monsters. Mega Man's a futurist battle robot who could probably keep up with the rest, he raids trap filled castles and takes down giant boss robots and robot masters. Pit seems about as strong. You could argue he beats full gods like Hades but I'd say only with the powerful armor the forge god made him. I haven't actually played the Earthbound/Mother series but if Ness can save the world and beat freaking Gaigas he and Lucas probably deserve this spot. I'd say the opponents these characters beat regularly are at least as strong as Bowser.
B
Bowser's a big boss but he often ends up teaming with Mario vs a bigger bad. Although several characters here are final bosses they don't seem any tougher than regular boss characters the tier above fights. Charizard and Greninja are lv 3 evolved pokemon and seem like they could fight Bowser but I'm not the most knowledgeable about pokemon. DK and Starfox characters go on adventures but they're not as dire as the tier above. Fox has gone on foot in SFA Dinosaur Planet and SF Assault but seems considerably weaker than Samus. I'm estimating Falco at the same level as Fox. ROB's based off Brawl's Subspace. The Kirby characters are hard to place since they live in a dreamland. I could accept them a tier higher for fighting demons like 02, Dark Mind, etc but they also get hurt by puny Waddle Dees. Dreams are inconsistent and metaphoric. Ryu is a strong tournament fighter but hasn't beaten legions of monsters. He seems super human but I don't want to put him any higher since it's always in a 1 vs 1 fighting style.
C
These characters fight weak enemies like walking mushrooms and aren't on the same level as higher tiers even though they go on adventures. Diddy plays second fiddle to DK in recent games but he could be a tier higher I guess. He's never been a boss like DK. Mario characters and Pac Man are more platform adventure oriented and probably aren't as strong of fighters. Their enemies just aren't as bad. CFalcon is a bounty hunter but for human-like characters and not huge monsters. His claim to fame is racing, not fighting. These pokemon are weaker than the others and not fully evolved. Zelda has the Triforce of Wisdom but she doesn't really do much in the games. Little Mac is a tough boxer but probably couldn't beat huge monsters.
D
Olimar and Alph are explorers and rely on Pikmin to do their dirty work. Peach adventures with Mario sometimes but also gets kidnapped more than any other character ever. She's often shown to be completely helpless. ZSS can only stun enemies with a fully charged paralyzer shot in Metroid Zero Mission. I'm just throwing G&W in here based on the little I know of his games.
E
These characters never actually fight that I'm aware of. WFT is fit but not prepared for an adventure like Peach or Olimar. Villager collects things. Duck Hunt Dog picks up dead ducks. Miis play sports and go to theme parks with stuffed moblins.
The IDK and don't care to look it up tier:
Their games have a lot of background and lore. I don't feel confident knowing where to place these characters.