Being me, I am of course obsessed with Gurihuru's redesign of Toph & the possible way Gene Yang may have written her. As I felt like I was going crazy (and thus like I would soon feel constrained to look at spoilers, something which I in my sane mind would prefer not to do), I decided to vent this into something semi-constructive and decided to analyze the differences in her appearance during the series and during "The Promise". I will attempt to try to make predictions about possible plot & character developments related to Toph in the graphic novel series from what I can wrangle out of the little information I have at hand. If one find what I have to say questionable, one can of course criticize my views in the comment section (though constructive criticism will naturally be taken more lightly than destructive)
In the series (except when trying to blend in with Fire Nation people), Toph Bei Fong wore a pale yellow tunic with loose green sleeves and pants, held together with a studded (leather?) belt. This reflects her mostly pragmatic allegiance with the Earth Kingdom in general (as implied by her participating in the Earth Rumble tournaments, which were meant to be an underground way of supporting their country without running in to trouble with the Fire Nation), as well as functioning as a way of expressing her toughened outlook on life, her glaring unwillingness to be associated with anyone else, any social group unless it brought something of value to her. In particular, the tomboyishness of her clothes & her lack of bothering to keep her hair out of her eyes reflected the fact that she had absolutely no use for the limitations society usually places on the female gender (practically speaking, why should she bother keeping her hair out of her eyes when she doesn't use them to observe the world around her?). The puffballs hanging on the sides of her headband reflect the fact that the over-harshness of this perspective is in part due to her age, put there to make her look like a cute little girl and thus point out that she does have a softer side that she generally witholds from view out of immaturity (and also retains due to the same immaturity).
To me, Toph's redisgn seems to resemble the color scheme of the Bei Fong family document to a great degree. Hence, I am also of the opinion that her new color scheme is meant to reflect a period in which she rebonded with Lao & Poppy Bei Fong after returning from running away; if this did indeed happen, it would necessarily have some effect on Toph's character in any well-written story. If they did indeed grow closer than they were in "The Blind Bandit", Toph would most likely feel a bit more secure in having a place in the world (which was perpetually unstable beforehand, on account of her parents protecting her like a fragile object due to her blindness rather than taking into account her needs as a human being), and would most likely loosen up a bit in the stance she takes relative to the rest of the world.
Keying off of this, the replacement of the studded belt with a yellow sash, seem to me to indicate that she no longer has to take such a single-mindedly toughened stance reative to the rest of the world (which the studded belt represented). Because of this, she would now have (partially) moved beyond of her emotional need to continually protect the equality of her person with sighted people via Earthbending, to the degree that she now is able to share the most obvious manifestation of this need (the development of Metalbending) with sighted people - and thus, for the more immediate purposes of the narrative, wears the belt as a possible symbol of her rank as a Metalbending teacher relative to her students. However, this does not mean she dropped her emotional reserve entirely, the studded bands around her hands and feet still working as (less apparent) symbols of her toughness (they were not studded beforehand, a visual service provided by the more obvious belt); it, however, hopefully means that she has opened up enough to allow her relationships with others to be less abrasive than they were in the show, enough so that she doesn't indirectly sabotage things for herself by accident on account of this (as was shown to happen more than once in the series, most obviously in "The Chase" and "The Runaway") - which could work to assist the development of any romantic relationship Gene Yang wishes to put her in in the graphic novels.
Her shirt sleeves are now held tightly around her upper arms (which emphasizes the outline of their lower portions), and her pant legs are now splayed more widely (more baggy, I guess) with the tunic's edges below the sash splaying along with them (rather than splitting between front and back, as in the series), which works to make her look more girly in appearance than she looked in the series (that, and the fact that the sash tigthened around her midsection emphasizes the fact that she has now passed puberty); taken along with the fact that she now takes the time to push her hair out of her face (a move which is useless to her, practically speaking), this would indicate that she is now less inclined to oppose the norms society places upon girls due to having had her place in the world now needing less protection on her part, allowing a softened ("feminine", if you like) stance relative to the world. The replacement of the puffballs with what Gene Yang called "dangly earrings" (though they seem to still attach to her headband, rather than her ears) alters in part the "cute" look given off by the former (even the dangly strands hanging of her headband were more puffball-like than what she wears now) in such a way that she now looks more mature than she once did; her softer side now theoretically being more open than it once was, it is now not in need of the non sequitur emphasis once given off by these accesories, and hence they are replaced to ensure that one takes the matured equilibrium between her toughness and her softer side more seriously (rather than say, always making her look "cutened", conveying that girls being tough like her while remaining free of antisocial perversion is naively idealistic and that her existence must always be a matter of condenscation to the audience of the show . . . which of course I hate, as an insult to one's intelligence & because it comes into conflict with my strictly non-sexist stance).
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