Doc > Samus > Ganon
Pika somewhere in the above but I have no clue where. Same for Mario. I'm not 100% of this, but I'm beginning to feel Ganon's potential is really bad just because he's a slow, easy-to-hit character that can be death comboed or trapped in awful situations for long periods. He has some death combos (both illegitimate and legitimate), a lot of gimmicks that give him really random first-hit potential, a lot of range (compromised by speed issue somewhat), and huge damage potnetial but it's really hard to get a grab on Sheik, or a clean stomp on someone like Fox (and having to guess on tech chases is really, really crippling; Sheik doesn't and her death combos are still far from guaranteed just because of human error, number of iterations you need to kill, slow damage build, etc).
Ganon with momentum is freaking great, though, and that would be (IMHO) what puts him above Samus. Samus doesn't really have the combo game or intimidation to really get the ball rolling in the same way that Ganon, Falcon, Fox, Falco, and others can. I feel that while Ganon can just get something rolling and crush the opponent's sense of self, Samus is more of a war of attrition and breaking them takes a lot longer (so, barring MU unfamiliarity, she's not good at beating better people or getting bullcrap wins). In exchange, she takes significantly more hits to kill, which opens up more opportunity for Samus to learn the opponent's style and/or find a way to outplay them. Ganon might die at 150% but if he gets combo'd to 60, trapped on a platform, combo'd for another 30, hit offstage, and then edgeguarded systematically (easy to do) then he's only lasted one, maybe two hits out of the neutral position.
Beyond knowing that Sheik ***** both of them and Samus is a lot better against the space animals, I'm not really sure what their MU breakdown is against the other significant characters. But I can't imagine either is good against Puff, I can't see Peach being horrific for either, and I lack the familiarity with the remaining two or three (Ice Climbers, Marth, Falcon) to really feel comfortable saying anything about (and there's a lot of variety on MU opinions for them, so I don't feel comfortable referring to anyone in particular either).
Anyway, regarding Doc being pushed up, Shroomed is honestly to blame for me thinking Doc is so high. His performances and strategies have really convinced me that Doc has legitimate answers for the vast majority of what the metagame throws at him. I feel he's sort of a weird middle point between Ganon and Samus in that he has a decent combo game out of throw, like Ganon, but also fast enough to react to certain tech situations without needing option coverage or whatever. He gets comboed by people, but not as hard as Ganon, but not as lightly as Samus. In exchange, though, I feel he escapes juggles (think Marth uair, Sheik uair, etc.) better than Ganon and Samus because of his lower hangtime than Samus, and his faster moves than Ganon. I also feel his aerials generally have more priority than Samus's, or stay out longer, and although it's sort of novel his Up+B finishing quicker than Samus's and getting him to platforms faster is situationally really useful for getting his jump back. His offstage recovery, I feel, is a bit worse than Samus's but the fact that he can attack immediately at low percents gives him a more flexible recovery mixup than Ganon (or Samus, in a lot of cases). I guess I feel that, despite his recovery being bad, he has more potential to be tricky with it than Ganon and Samus (okay, maybe not Samus, but certainly Ganon).
Pikachu is tough as balls to fit in because I feel he should get ripped apart by Sheik but if he doesn't fight a Sheik, he's actually got some good gimmicks and high damage output potential to really put the hurt on most characters (even Sheik). His total inability to approach Puff and Peach if they play super gay is troublesome, though. Ice Climbers also seem very nasty to him. Mario is hard to place because he feels like a Doc with a watered down chain grab, an f-smash that's useable as an approach or defense (but overusing it invites baiting; it's not spammable by any means and it's easy to evade-punish with fast characters, or if you're just out of his range), a more reliable up tilt (but the horizontal hit on Doc's often enables an edgegaurd or gimp setup, which can be potentially high momentum shift, and the launch is still easily doable during most combos or vs high approaches), worse gimping, arguably worse projectile, better recovery, and a worse up smash (Doc's up smash is freaking sick). These differences range from important to small, with small generally being more dominant, but thats a lot of small differences and they do add up. I think he's below Ganon at the moment, but I'm really not sure.
Following that, in a lower tier, I have:
DK > Young Link > Link
Mario is definitely better than those three, same with Pika because duh. Chain grabs with moves that hit while facing front and back, real anti-air moves when grounded (Mario), nearly dirty combos (Pikachu more but Mario too), and gimping (Pika more but Mario too) make them better. They're also better at camping fast characters than the Links because they don't rely on slow projectiles to limit approaches.
I currently have them in that order. DK just because I still think he's significantly better vs Fox than the Links (still horrible, though) but that's subject to change (maybe put him in between the Links?) because Young Link is more suited for floaty MUs and I think his counterpicks against non-space animals are stronger. Normally I'd say FD is gonna get banned anyway so it's not even a real point for DK, but I also have super secret MBR information that affects such an issue so it's a legitimate point (or will be, shortly, kind of). That's about as obscure as I can go, I think.
Young Link greater than Link in this meta, I think. Link is better against approaching characters like an aggressive Falcon or Fox, I feel, because of his greater KB that induces knockdown or combos earlier. His range also covers more space, which allows him greater flexibility in beating approaches from a stationary position. His range matters a lot. I think his younger alter-ego is more equipped to deal with camping characters because he has the speed to not get shut out by them as hard and also outcamps the floaties pretty hard.
Zelda is still difficult to place because her MU spread with good dash dance camp characters is really dynamic. Against characters with good dash dance games and high tier status or greater (Fox, Falcon, Marth), her MUs are worse than 80-20 or so if the opponent plays super duper gay and refuses to get hit by this slow horrible character (this isn't unanimous; I just believe Mow when he says Zelda is as bad as he says he is). And her Sheik MU is comparable bad to those three (it's better, probably, but still like 80-20 or so). But after those four MU, nothing is really unwinnable or horrible. Whereas a lot of low tiers like Bowser or whatever continue to have horrific MUs until they reach the bottom of the tier list, Zelda literally goes from 80-20 nearly unwinnable to 60-40 disadvantage or better with nothing in between. I feel if you can somehow only get Falcos, Peaches, and Puffs she's arguably better than Young Link, but unfortunately Fox is still the most common character. Still, in a different meta, she seems like she could be pretty high up (even if unfairly so).
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