well, your concern is legitimate and more aboriginal characters are welcome in media
however nothing you drew really reminds me of aborigines at all. They're just anime girls in swimsuit.
Of course, an ethnicity becomes harder to portray in anime styles, but with a quick look on google images, most girls seem to have rounder faces (in contrast to your long face drawing), wider and rounder noses (rather than just big and pointy) and a very definite eyebrow angle (they all seem to have a slightly 'angry' expression due to the angle of the eyebrow). [details like ear placement, eyebrow angle, eye shape/position, nose size/shape and head shape all vary depending on ethnicity]
this is just one stock photo and of course it only serves for facial reference, you'll get better results the more you research. I'm just saying that your characters really don't look ethnically aboriginal.
Also no matter the ethnicity, please avoid drawing tiny Y on breast cleavages. Those only appear if someone or something's pressing them together fiercely
No Y cleavage!
Not to say that professional swimsuit models don't leave space for breasts because it ruins hydrodynamics, as seen here
ofc if you're going for full anime aesthetic you can ignore physics altogether
(once you confront more realistic images, this anime swimsuit becomes glaringly problematic)
anyway i just gathered some stuff that could be interesting for you to have in mind, it's cool that you feel happy with your work
however nothing you drew really reminds me of aborigines at all. They're just anime girls in swimsuit.
Of course, an ethnicity becomes harder to portray in anime styles, but with a quick look on google images, most girls seem to have rounder faces (in contrast to your long face drawing), wider and rounder noses (rather than just big and pointy) and a very definite eyebrow angle (they all seem to have a slightly 'angry' expression due to the angle of the eyebrow). [details like ear placement, eyebrow angle, eye shape/position, nose size/shape and head shape all vary depending on ethnicity]
this is just one stock photo and of course it only serves for facial reference, you'll get better results the more you research. I'm just saying that your characters really don't look ethnically aboriginal.
Also no matter the ethnicity, please avoid drawing tiny Y on breast cleavages. Those only appear if someone or something's pressing them together fiercely
No Y cleavage!
Not to say that professional swimsuit models don't leave space for breasts because it ruins hydrodynamics, as seen here
ofc if you're going for full anime aesthetic you can ignore physics altogether
(once you confront more realistic images, this anime swimsuit becomes glaringly problematic)
anyway i just gathered some stuff that could be interesting for you to have in mind, it's cool that you feel happy with your work