Seong Mi-na is the mobile character with a polearm. This is what makes her unique.
This lets her do big damage and be lethal, yet she can swing the weapon, and move herself around, in ways that Zasalamel and Astaroth cannot. She has a blade where Hilde and Kilik only have a 'point', but realistically, Kilik is always going to enjoy perks and be able to slap opponents around, nothing to do about that. (Theory: Hilde got out of hand the day she was given non-thrust spear attacks? It's in her doom combo after all). At least, she should have the advantages that all four of these characters have over the zweihander wielders. (Astaroth's body e.g. 66K is a top tier weapon, so he'll always be inherently strong, sure.)
'Mobile' stands for 'quick' in some sense, it's the same thing. I mean moves like pogo stick, B+K, A+K, or FC 1KK. Astaroth could never have any of these, or FC 1B. Only Mi-na's weapon gives her the freedom she has, yet with the length (thus leverage) it has. She is a Talim that wants to not be standing right in front of you, attacking forever (more or less), like Age_of_Truth said.
In SCIV you have SG damage, and safe lows when spaced. The safe lows thing probably ought to stay on, but it's just a factor of her 'risk-reward rating' when in good zoning, as far as I'm concerned; one thing among other possibilities to make her moves "good." As long as these ideas guide Seong Mi-na design in SCV, I think she'll be okay. That is, provided buggy ghosting crap is removed, as it should be from all characters of course.
For all characters, my wish for SCV is nothing but to make the moves make sense. I've replied in the Nightmare and Raphael threads of the same sort. It's "To put into the game, all the mechanics that let what makes the weapon style actually work, in reality, do work in the game." What you add on top is why the game becomes an amusing fantasy (and yes, you have wholly unreal characters, so you add some other 'bonuses' so everyone goes beyond reality to the extraordinary; you also make sure not to 'limit' a character merely by typical 'weaknesses' of a weapon, though that does help guide matchup tweaking). The claim I'm making is, I suppose, the same as saying Mi-na has garbage, slow, nonpractical stuff, as page posted back on page 1. We're both saying the fundamentals have been ignored by the designers.
(page then said if bugs were fixed Mi-na would be passable; not sure what to make of this)
So, some specific stupidity:
66A and 3A. Neither one is actually horizontal. wtf. Neither of these moves may appear in SCV, but, I think these two moves summarise Seong Mi-na's horrid issues with tracking in SCIV, and consistency between the moves. 66A TCing and not tracking makes sense, a hori is how you would get a crouching mid with that weapon and have power, and even the + frames makes sense as the goal is obviously to get close. But you put it beside 3A, which is so much worse in properties, and not much more gain, and you ask... why is Mi-na doing that move? Why not do -anything- else? 33A when you would 3A.
6AK: Really. It's like some programmer put the 'force crouch on crouch hit' property on the wrong line. As for what to do about the move, to me, it's not about where that property is out of place, it's about the logic of having this mid-high sequence. -Why- would Mi-na attack with the butt of the weapon, 6A, just assuming it would be minus on hit (assume)? For speed, presumably. But speed without range, and intentionally putting the business end backwards? This is the strangeness; 6A was backasswards for Mi-na from its conception. To want to have a weapon attack to interrupt weapon attacks is well and good. But beside her kicks, she has two aGi moves for weapons, and is naturally good with advantage from block anyway. In sum, she has the bigger weapon - you get creative up close and you can overmaster anything a smaller weapon can do, but you need to play for high reward. 6AK shouldn't have existed. Given that it did, the natural sequence would be to cancel 6A into a pressuring but slow move (i.e. frame trap on hit), or heck a grab to mixup.
See? Intuitive design direction solving a problem. Just look at her grab animation and her 6A and it'll hurt wondering why she doesn't do it. And when you think about 6A like that, it's not that the K is high and stupid, it's that kicking after that attack weapon movement makes no sense whatsoever; the frames and "NC" label confuse this point. Until you crank up frames to 'abuseable', a stupid move is a stupid move.
That's all I've got to say for Mi-na.
@Yubashiri: Kilik is a Seong Mi-na clone. Wikipedia tells me she was here first.