No.321
even if your hair is the right color, getting a wig is always a good idea! your natural hair looks fine but if you plan on cosplaying Sabitsuki more in the future you should really invest in a wig, it'll be worth it and they are much much easier to style! as well, I'm not too sure about that little black belt on your skirt but that is just my opinion, it looks great otherwise.
No.323
Could use a "frillier" skirt, too, for lack of a better term. I'm no expert on skirts, but Rust's skirt has some pretty clear folds in it, and I assume Sabi's is just as "fold-y".
Oh, and for future reference, if you're cosplaying as a .flow character, your character is left-handed. No exceptions.
No.329
Pretty cool cosplay! Although, in the future, I reccomend trying to do more of a bed-head-ish style instead of a straight style, since that's what Sabitsuki's hairstyle is. But, if that is your natural hair, I reccomend getting a wig. You can get it to the proper length, and the absolute proper color.