I recently had to change the bladder in my 2009 10m rise.  I noticed that the zipper opening is pretty small - i could barely get my hand inside the LE.  On my old kites (another brand), the opening was much bigger, big enough for me to put my whole arm in.  This was really handy for sewing on patches without having to open up the LE.  Maybe you’ve already addressed this on the 2010 and 2011 kites.  If not, maybe you could consider using a bigger zipper opening on future kites.

Good point.
Why is it so small?

The zipper openings are the size they are because they are a weak point in the LE tube. I also try to keep them away from too much contact with the canopy (while laying on the beach) to prevent wear.