first, I would not iron fleece and I probably wouldn't starch it either (but then I don't starch anything). I think 8 inch blocks would work fine but would require lots of seams, which take away from the amount of usable fleece left. and the seams get bulky. Instead of traditional seams, you might just overlap the blocks about a half inch and stitch down the center of the overlap. This method uses the same amount of fabric, but without the bulky seams...and the result is reversible. A small zigzag would work well since it builds in some give for when the fleece stretches. Also, since fleece doesn't ravel, you could cut the edges of all blocks with a wave cutter - or pinking shears - to give them an interesting shape to the edges.