Actually, I would agree to put H-S.Akiha up a few tiers. I'll give some reasons:
1. Her IAD pressure is extremely fast.
2. Her dash is extremely fast. It allows for ridiculous tech punishes. I mean, she can literally tech chase people on reaction.
3. j.BC dj.BC combos on a standing opponent if it hits, and is her fuzzy guard, leading to 6.5k damage on hit.
4. 2A 2B 5B 5C 22B is a godly frame trap. It allows her to continue pressuring with 2B etc... and can then lead to 5B 5C 22A/B on block. The mixup here is the opponent can jump out or mash out of her 22B, however, 22A catches jumpouts/mashing. This then leads to jumping out/mashing after the 22A. I'm not sure how safe it is, but I know that 22A is atleast safe on block. 2A beats mashing, 6B beats jumpouts.
5. 623C is a fantastic reversal and sets up for tech traps if it lands.
6. Her arc drive is completely safe on whiff or block. It also gives her really good pressure if she's rushing down, giving her the threat of putting it out to catch mashing or simply as a throw setup.
7. Her command throw sets up for oki and is a viable threat when you need it. I've won sooo many games from turtling players by simply throwing them and setting up her ambiguous cross up/guard break.
8. She has an ambiguous cross up/guard break midscreen from throw or combo. The combo that sets it up is 2A 2B 5B 5B 5A 6AA 22A 2C 22A. This allows her to super jump past the person that just got comboed, and airdash j.C. If you time the airdash correctly, you can either cross-up or not cross-up. That being said, if the opponent tries to jump, her j.C will keep them in place in the air and S.Akiha can 2A guard break. This doesn't work on some characters, and on some characters you need to use ad.B.
9. Her j.B has ridiculous range beneath her. It is a great air-ground poke. j.A is also a really good air-air poke.
10. Pillars are great for setting up throw attempts in the corner for oki.
Now, she does have some problems, too. She has absolutely horrible match-ups against Riesbyfe and Ryougi because their attacks will outzone her all day. She has to be liberally patient in order to get in and force them to block. Even more so, Ries can reversal to get S.Akiha off her, making it really hard to stay in. S.Akiha's mixup game aside from her oki setups is pretty garbage. However, if you are good at punishing players, you can force them to block for a very very long time in the corner using her 22x series. (I've gotten many guard breaks this way)
I think she should be pretty high, but I wouldn't place her any higher than A.