I'd like to add to what 4r5 said earlier about the Potemkin and Ky matchups.
I did already kind of say this, but you really need to use f.S in this matchup. You don't want to jump if you don't have to, because even if you are out of his anti-air range, you're still making a stupid commitment that you simply don't need to. If you ask me, the best way to play this matchup is to stay at f.S max range. Walk forward, walk backward xN is the best way to turtle, since you build meter and you'll be ready for anything as opposed to jumping which severely limits your options.
At your f.S max range, Pot has to make stupid commitments to hit you or he has to approach either by walking forward or jumping in. The game you're playing vs Pot is almost entirely reactionary, and the moves you're looking out for are Slidehead, Hammerfall and jump. If he does Slidehead, either jump or (wave)dash in. If he does Hammerfall, just block. If he jumps, move in and anti-air him (Upper Mistfiner, airthrow) if you can.
But what if you don't react correctly? Well, if you whiff f.S because he did Slidehead, you're fucked and that's all there is to it. Sorry! If you don't like it, play Eddie. If he did Hammerfall, however, you can cancel into a coin (and only a coin) and hit him out of superarmor if you react early enough. If he jumps in, depending on whether he did a normal or super jump, you either block or SJ and airthrow him.
While j.S is good in this matchup, I feel that you unnecessarily give up your control on the ground if you use it as your main poke. Not to mention, you don't have anywhere near the damage potential if you use j.S instead. What I like to use j.S for are the situations where you're forced to jump (such as if he does Slidehead) to cover myself on the way down.
On a side note, if you still can't confirm f.S into Mist Stance Dash Jackhound, you're going to have to if you want to beat Pot. If needed, I can make a thread dedicated to MSDJ.
Overall, I don't think this is nearly as bad of a matchup as we all used to think it was. 6-4 sounds about right. Pot has to respect your f.S or else he just gets counter hit to death. You do still have to deal with annoying crap like 1f vulnerable backdash and Pot mixup in general, but as long as you can keep him at range there isn't much he can do without taking a stupid risk.
As for Ky, I think 4r5 more or less had it spot on. However, he left out a few things.
First and foremost, you really want to learn how to wavedash. It's a great way to close the gap on him when he whiffs something.
Another thing is that j.S and j.HS are both great in this matchup. Allow me to explain.
If you jump against Ky, you want to neutral jump. This keeps you out of the range of most of his anti-airs and actually puts you in a good position. One thing I like to do vs Ky in the corner is end a typical blockstring (5K 5HS MC) and then neutral jump to see what he does. If he does something stupid like Stun Dipper or f.S, just j.HS and kill him. If he throws a fireball or jumps, j.S (or airthrow, depending on how he jumped).
You only want to use j.HS at its max range, though. I cannot emphasize this enough. Ky has six fucking anti-airs for crying out loud, but if you space your j.HS correctly they will ALL lose. If his 6P is clashing, you're too close.
j.S can be used a little more liberally, but you still want to stay around its max range. And of course, don't use j.S if you're in range for him to 6P you. Because if he can do that, he can do a ton of other things, too. In fact, if you're that close, why are you even jumping?
On the ground, you don't want to poke that much. You mostly just want to IB every fireball he throws and force your way in by walking forward. Don't mind getting hit by f.S or Stun Dipper or anything like that, it's just what you have to do. As long as you don't get hit by anything that leads into damage (lol Ky), you should be fine.
Once you're in, it's all 5K and 2S. Maybe 3HS if you're a jerk and wanna call him out on Stun Dipper. But don't do that, that's silly.
I still hate this matchup, because it feels like for every commitment you make Ky has 2-3 ways to beat it that overlap with your other options. But if you're patient, you can get in and kill him. 6-4 sounds about right for Ky, too.