Rayon blends are probably the coolest low maintenance material. Some thin cotton weaves also dry fast (tissue weight). Polyester can be hot but never ever wrinkles. A polyester blend is nice. Tencel is very cool and easy maintenance. I test for wrinkles by taking a handful of material and crushing it. It should fall back out with no wrinkles. It isn't just the material, but the weave that makes something wrinkle free.
I like to take technical pants because I hike a lot. I prefer Royal Robbins pencil pants. Sierra Trading Post has many discounted tech items.
Most of my other clothes are knits from Dress Barn, believe it or not! I have an Athleta skort that I love. I have begun to love the Portofino blouses from Express. They are a light crepe with roll up tab sleeves - wear them short or long. They come in regular and slim cut, plain and patterned. I've also found light weight tees and maxi skirts at Target.
Focus on neutrals if you want the biggest bang for the buck. If your pants, sweaters, and most of your tops are in neutrals you can add scarves and statement jewelry to make things pop. I like to bring one or two pattern tops. A two piece dress makes more combinations than a regular dress. I have started playing with pattern matching - bringing a top and skirt that are patterned but "go" together**. (A navy polka dot top and a stripe skirt for example). A 3/4 sleeve tee goes over or under another shirt. Can you roll the pants up into a capri look? All of these give you more looks without more clothing. Also make sure you wear a different top from the day before. One last thing - make sure your bottoms are darker or patterned. You sit in a lot of "stuff" and dirt will show up on really light materials.
Uniqlo has a lot of inexpensive travel ready wear too, such as light weight down jackets. I abandoned my fleece when I found my Patagonia nano-puff. BTW, you can find a lot of great items on e-Bay. You can set up searches for them.
Pick up the clothing under consideration. It should physically feel light. If not, put it back even though it is a knit or synthetic. Heavy items take a while to dry.
My favorite list for clothes:
1 button down roll up tab shirt (like the Portofino blouses)
1 3/4 sleeve light tee
1-2 short sleeve knit tops
1 bonus top (print or pretty item)
1-2 light sweater (thin)
2 pairs of pants - one that I can roll up the legs
1 skirt (if the skirt matches one of the tops, BONUS)
2 scarfs (in summer 1 scarf)
2 necklaces (1 colored statement) earrings, light bracelet
1 good pair of walking shoes (I like the euro style athletic shoes that look like bowling shoes but have great treads)
1 good pair of dress shoes that I can walk in. Sandals in summer, ballet flats most of the other times, dress booties in dead winter
leggings (wear under pants or with skirts when cold)
silky tee to wear under shirts when cold