I would quilt lines radiating out from the centre of each star to the points at maybe 1/2" scale. You can use rulers or draw it on without needing to buy/download stencils. Check out here:
http://www.youtube.com/watch?v=KwVIzPUX4pk
For the background, I tend to like this one:
http://www.youtube.com/watch?v=tlDlKpx2NTc
but if you really want pebbling on the background you could try this one:
http://www.youtube.com/watch?v=bmN9WufYyH4
OR treat the backgound as a 2ndary pinwheel design and also quilt with radiating lines.
HTH