Polar fleece is better for sweaters. There are many materials that can be used to make sweaters. You can refer to the material of the sweater you wear every day. However, polar fleece is thicker, which is commonly used in spring and autumn clothes.
If you don't wear polar fleece often, you won't pilling a lot.
Personally recommend sports fabric or cotton blended fabric? The latter is more suitable. Polar fleece ... it depends on what season the character wears this dress. If it doesn't work, shake the fleece.