A Merry Christmas and Happy New Year Anon!
>>130All the girls posted are 1/4 or 1/3 Dollfies so too large for your <30cm requirement. Getting faces of similar quality at the smaller scales can be pretty difficult as Volks doesn't offer that size in the same styles.
I'll assume you are only interested in vinyl girls and it sounds like 1/6 will be the sweet spot for you. I have no experience with that scale but from my understanding there are two major players (they both use Obitsu for manufacturing though which is a very solid vinyl doll maker so no worries on overall quality).
The king of 1/6 dolls in Japan is Azone. They have a few ranges but basically you'd want a Pure Neemo body which range from around 18cm to 23cm or so (before including the head). They have premade girls but the prices are relatively high, around 14000 yen depending on the series. They are really popular too so a lot sell out quickly. I don't believe they have a customisation option with standalone heads but I may be wrong. Biggest downside is their eyes are always painted on. Azone just recently started doing physical eyes on their larger dolls but are not doing it for smaller scale yet. Here's some info in English:
https://www.azone-int.co.jp/us/ You'd have to buy them from Hobby Search, Amiami etc or a used one on Mandarake.
If you want physical eyes then Parabox may be the better choice. I don't find their head sculpts as cute but their site is completely in English with international shipping and they basically let you fully customise the doll from a few makeup options, eyes, wigs etc. Their sizes range up to 27cm bodies in the 1/6 scale but for range of outfits sticking to 24cm might be better so you should be able to buy from Azone as well (I think the 24cm Parabox lines up with the Pure Neemo body but you'd have to check that, I read someone say that a 23cm Obitsu was too small to wear Pure Neemo S clothes which seems weird given the listed sizing). That will also give that more childlike look the last two images included have. Parabox is very wallet friendly for this hobby. Here is their guide on ordering:
https://paraboxshop.jp/contents/en_JPY/paradoll