With all do respect of course, I do not really care what the pagan and heathen think on this matter..
With all due respect; sometimes it is good to know what the "pagans" (As you have written off the people groups I have mentioned as a whole) have done, is because we are told to not do as the pagan canaanites and the egyptians did before us.
Shaul basically tacks on the Romans and Greeks (and the peoples brought into this pagan grouping) in that broad brush... so yes, it does help to know what their ideas of modesty are, because many of us have grown up through these people groups.
Myself, I have a lot of celtic blood by way of my Jewish ancestors that came from these lands, as well as German ancestry the same way, and Cherokee... so I got a lot of baggage to shift through to find back "In the beginning" - "What were we explicitly shown about modesty and what it is and isn't, and what has to be covered and how?" --
Because, whether we believe it or not, when we grow up in the western world, we filter *EVERYTHING* in scripture from our western mindset whether we realize we're doing it or not.
We think in terms of our culture rather than the culture we should be thinking in terms of. We think of "what about our clothes?" Rather than "What were their clothes?"
Clothing "back in the day" until the middle ages were pretty standard for men and women. Some kind of robe, and in colder climates, some kind of "trousers/pants".
Considering how trousers/pants came to be, and who wore them, how and where, we find that even wearing them with a short shirt [for a man] was once ""Scandalous!!"" It was thought better to wear the tunic and tights, or the "robe" than the trousers for modesty's sake.
In Japan, the ideal modesty is concealing *all* of a woman's curves... but exposure of the upper shoulder and nape of the neck is considered beauty and acceptable, as is the exposure of the elbow to wrist area as well.
However in predominantly muslim countries, a woman can wear what she will under her burka but must be 100+% covered when she leaves home.
And the more research we do, the more we find differences in the Roman and Greek dress and our people's, and that no matter where our people went, that we dressed predominantly the same, though the styles changed.
Collar bones were generally covered on women, shapely is fine, but make sure the clothes are loose and not clingy, and that elbows and knees are covered. headcoverings are a plus....
Moving into the time from the 1700s+ in Eastern and Western Europe, the wig was approved as an appropriate "headcovering" (i still don't get it, but one day I guess I will).
We find the same in the countries we went to.. all over the world, our people stayed "set apart", and some assimilated. It's hard to break out of assimilation, and in so doing, it's good to research to find "what did the canaanites do that was so bad on the modesty scale as well as the things that made them be spewn out of the land?" - and we find evidence scattered all over the scriptures.
it's also great to find out what our people did where they went..
We find evidence of that in the rabbinic writings, and some in roman and greek and egyptian writing about our people- how they dressed, how they acted, what they ate, what they did... and in european writing and law about us.
There's a clue where to go and how to get back. It doesn't have to do with wearing feed sacks or baggy clothes or burqas... but being modest in our attitude and heart first, and clothing will gradually become more modest as our actions change.
If a man dictates how a woman should dress, you will find women pull back from the idea. But, if a 'mother' (spiritual or physical) helps disciple a young girl and show her modesty, or if we bother to do the research ourselves, we will modify our wardrobes accordingly and without problems.
It used to be easy to get clothes because everyone made them... all you needed was a pattern and fabric and the supplies, but many of us have lost that art, and clothing fabric is pricey and hard to come by! ..'tis easier to just buy ready-made, and not all of us can afford 100% cotton clothing in our sizing. it's hard to find and hard to afford, so you do what you can, and with what convictions you have.
As convictions change, so do your clothes, food, holidays.. etc.