Those are four major factors, taking into account all of a character's recovery options rather than just the up special, of course. It's also worth considering mixup potential, or how many movement options a character has in the air at a given time.
A major reason
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and
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's recoveries are among the worst is because of their linearity. There's only one sequence of moves either one can really do in the air to get back to stage, making them extremely predictable. Conversely, even though
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doesn't have good amazing options for distance, he has a lot of them, particularly if built for it. Soaring Axe Kick + Burning Drop Kick + Feint Jump means he has many different movement options making it back to stage (granted you don't see all three run very often).
You're right, I forgot about that consideration. A recovery is certainly more than just a character's up B. Options are important, which can certainly come from moves like side B or multiple jumps, or in ZSS's case, down B or a tether grab.
Peach literally has the best recovery, its basically invincible and not talking about the parasol. Kirby and Jigglypuff have very reliable recoveries and theoretically Ness. Pit, King K. Rool and Diddy Kong have very good recoveries.
I think I'd have to disagree on Krool's.
A friend of mine plays Krool a lot, and we regularly fight. I always, always always abuse his recovery really hard. It's one of the easiest recoveries in the game to intercept, in my opinion, as he comes up quite slowly and is vulnerable to attack from the side during the entire process. He can't recover well from horizontally out, as his recovery will overshoot the ledge, which usually leads to him being KO'd. This makes his only option to recover low, opening him up to easy bairs, fairs, or other moves that can get around his propeller. He also has no other moves or extra jumps that would help this situation.
I make quick work of off-stage Krools online as well for the same reasons.
I'm not too familiar with Peach. I've fought her a few times online, but don't really know any Peach players and don't know what options she regularly has available for recovering.
Same with Diddy. I'm not sure what he's capable of.
Kirby and Jigglypuff definitely have good off-stage mobility, and decent aerials to protect themselves. Jigglypuff's vertical mobility can be a bit limited, as she can't go very low below the stage due to limited jump height and no up B like Kirby has. These characters can be intercepted off-stage, as they're quite floaty and don't really have any free get back to stage moves (like Palutena, for example, and her teleport).
If they were to be placed in a tier list, where would you place these characters?
I'm hesitant to put some of them in A tier, as usually when I think of A tier, I think of "I cannot challenge this character off-stage or gimp their recovery at all" kind of tier. These would be characters like Palutena, Pikachu, and Pichu.
I'd probably go with:
Peach (taking your word for it), A tier. Doesn't surprise me given she's regularly placed very highly on general tier lists.
Kirby - A- / B+ ' ish, I've definitely been able to kill off-stage Kirbies but they're a very real threat
Jigglypuff - B - limited vertical height and no recovery-based up B hurt her a bit, but she has tons of jumps. Very floaty / easy to hit off-stage though.
Ness - C - his recovery is shorter than Lucas', and he can be hit out of it pretty easily. Nonetheless, he has a great air dodge, fast air movement, and falls slowly. I always die when I try to use this move lol.
Pit - A - Three jumps, far-reaching up B, and his side B can help recover horizontally. Definitely has a great recovery. Also has a counter-like move that may be useful for protection.
Diddy - no idea
Krool - C - one dimensional, slow, and highly abuseable. I disagree that he has a great recovery, but its' still 'ok,' which is C.
Ganondorf - D-. Not as bad as it could be, but he certainly doesn't have a very good recovery. He's pretty easy to gimp, and can regularly be hit far enough off-stage that he simply cannot make it back.
Dr. Mario. Not too familiar with this character. I've heard he has a lousy recovery though.