I'm going to make a crazy ridiculous suggestion and say that the way that this game will evolve is toward keeping the pressure on at their preferred spacing distance in some way, and capitalising on your opponent respecting your maintained pressure at spacing distance. As people get better at the game, they will get better at spacing, and the less that "Make them block neutral assist, do up close mixups" will be the deciding factor in the game.
Characters that can maintain distanced pressure: Peacock, Big Band, Eliza, Parasoul, Fukua, Cerebella.
Characters that can't: Filia, Valentine, Ms Fortune, Painwheel.
Squiggly: It's a travesty that I have absolutely zero first-hand experience with Squiggly so I have no idea how to categorise her. IM SORRY I SHOULD LEARN HER SOON
Everyone in the second list has this thing in common: They MUST get in through movement and positioning, OR whiff punish to get their game started. Counterpoking is something that must be done with movement ie Filia IAD. This means they will have less consistent play in Neutral game without assists being a get-in-for-free card. They do have great frame advantage once they get in on their lights and lows, and Airdash/Flight opens up more avenues to get heavy frame advantage into strong high-low-left-right mixups/pressure. They also have greater capacity to set up pushblock baits with empty airdash->throw, but one correct super/reversal read or PBGC or Reveral assist call and they have to make their way back in again.
The advantage of being a character in the first list, is that you don't have to play in a range where most reversals can reach you if you don't want to. This makes people not want to use reversals. This lets you condition your opponent to calm their shit and respect your space control, to THEN run in and do a mixup if you so choose.
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Specific notes on certain characters:
Valentine: Her entire strength is the ability to ignore regular attack vectors, and dive in from weirdo angles that you can't do SHIT about. I believe that players who are doing poorly with her are treating her too much like Filia/Ms Fortune, and need to run away WAY more, and pick their spots VERY carefully, and most importantly pick a great neutral assist. I think her falling off is just coincidence of higher level players not playing her, or people not picking her up because people were all like "Well, Duckator is the best player, and he uses Val, I'm not gonna pick Val because playing top tier is boring!!!". If she had a plus on block c.LK, people would complain about Val far less, I think, but having a -4 on block c.LK kinda makes it fair when you can make people block shit from wacky ridiculous vectors.
Valentine is not quite a raw mixup character(BackdashAirdash shit notwithstanding), but she is a character who can make you block something easier than any other character in the game. EDIT: Shit I almost forgot, Valentine actually has a very strong capacity to counterpoke with her normals(j.HK, s.MP come to mind), compared to the other characters in her category. But still, she can't maintain spaced pressure with her normals, she always has to either go in or go out.
Painwheel: Painwheel has issues at neutral, yes, but she is the strongest character in the game once you are made to block something. Miles ahead of every other rushdown character in regards to being able to pushblock bait, deal with reversals/supers with j.HP into thresher on reaction, and make the opponent not want to do anything at all. Her raw mixup isn't as potent as Ms Fortune or Filia, but Ms Fortune and Filia do not have even remotely the same capacity to reset their pressure as Painwheel. With the capacity to reset your pressure, comes more tick throws, and painwheel can convert off of her tick throws everywhere in screen without meter without otg if she doesn't want to, which the others can't. I can not think of a single character who is as good as she is once she gets in.
Peacock: Peacock is a lockdown character, whose lockdown tools just so happen to help her zone. If you can get in, stay in and run mixups that you can turn not only safe but positive every time. If they get blocked, do LK George. If you get pushblocked, call another M item drop. When she puts so much shit on screen, she MAKES you respect her which lets you run Peacock's kinda okay mixup game to devestating effect because you don't have to worry much about people mashing jabs or reversals after they get item dropped at frametrap timing for the 500th time, or eat a long range c.HP, or eat a plane, or any of her other shit she can put on screen. j.MP is a fantatic air-to-air button that stops aerial approach and can chain into j.HP as an extra level of fuck you.
The moment Peacock gets ANY kind of momentum, and sets ANY of her shit up, she is incredibly difficult for every character to deal with.
Big Band: L Brass needs more abuse, it's really good for neutral. M/H Brass + Neutral assist that keeps it either safe or plus is stupidly braindead. He walks you to the corner if you want to block brass, and counterpokes your approach if you want to get in. As Big Band mains get better at parrying, he will be less free to pressure/neutral game rushdown openers. Every confirm can turn into a hard knockdown that sends them fullscreen and then some. His close lights are quite plus so his pressure is actually really good once he get in, everyone needs to do more frametraps. j.LK->j.MK fuzzies are also great. L Extend is a game changing assist. I personally think that Giant Step is a bit of a gimmick mixup option, but the light one is great up close. Keep an eye on him.
SIDE NOTE:
Every character that has the capacity to set up an air throw/burst bait 50/50... be very very very afraid of them once they land a hit.
