Although I often tend to dress the opposite, I have always appreciated the simple and clean lines of Uniqlo's clothes. There is something soothing about going into an Uniqlo store and seeing those (usually) several floors filled with color-organized clothes. Not to mention the sheer practicality of the design which is constantly being perfected.
Here is a combination that would work great with both flats or heels for a more sophisticated look (I would personally choose the burgundy skirt, for the color and texture).
But what I also like about Uniqlo, is that they often do collaborations with famous designers who then bring a bit more color and patterns than Uniqlo would normally have it. This is from a recent collection of Celia Birtwell - for some reason these tops remind me of cupcakes! :)
Click on the image to go to Uniqlo online store.