When we finally got our new window seat upholstered last year, we bought two acrylic rugs to cover them up and didn't even buy proper cushions. Just bought some red pillowcases and put them out. After awhile I admit I don't notice these things, but it drives Rob nuts!
A few weeks ago we came up with an easy solution (not sure why we didn't come up with it sooner). We bought 3m of the red gingham fabric and the same length of red polar fleece. Then last weekend my personal seamstress (Rob) hand stitched the two together. I found some red themed cushion covers and we put it all together on Friday. We're pretty happy with the new look. The cover can be removed and washed in the machine easily.