I know it's just my taste and the fact that I went shopping today in a thrift store in a suburb of many older Christian women, but I got a little annoyed at just how many pilling knit shirts and synthetic sleeveless-blouse pieces I saw. Usually some floral pattern or solid saturated color. Why is it so difficult to find neutral colors and natural fibers? I like the linen things that are so much more common in Asia.
As an aside, those things (loose linen shirts like you said) are really good for hot humid times/places. Anecdotally I think cotton and woven materials in general are lighter, more breathable, and more water-permeable in general than synthetic and knit materials. I figure there's a reason Korean fashion has so much light colors and woven fabric: it both protects you from the sun and allows cooling. Similarly, construction workers often wear long sleeves and long pants to protect from the sun because when you're out there that long, the cooling benefit you get from direct contact with the air gets negated by the direct contact with the radiant (radiative?) energy of the sun.