Love your quilt, and your courtesy of thinking about where they live.
As to tying: I've done it at the distance stated on the package. It wasn't enough and the batting bunched up. I'd recommended tying at 1/2 the distance. Also, the movement during use and washing put a lot of tension on the tying spots and some tore the fabric. So again, I reccommended tying at 1/2 the distance. And tying across seams or intersections where there is more fabric to give more strength.