In addition to some line and water purification as was mentioned, here are a couple suggestions off the top of my head:
-Add a quality whistle
-Consider spare battery for that light
-Replace the small kitchen bags with either a bivy sack, or at least a heavy duty large garbage bag. You have the bladder in the pack for water already, you need shelter. Trash bag can also be a poncho.
-Rather than 2 lighters, maybe 1 lighter and another different type of fire starting device. A small quantity of firestarting material (you could use the tissues and hand sanitizer of course, but, I'm thinking a few vaseline cotton balls or some premade starter material, and maybe a chunk of fatwood)
-Wire or heavy fishing line or maybe a few zip ties
-You could probably put a few additional first aid supplies in the space that you have the blister kit.
-Compass, and trail map for where you are hiking
-Small bottle of insect repellent, maybe sunscreen
-Sunglasses, unless you are already wearing them
-I assume you'd wear clothing appropriate to the hike, and could layer on and off.

I'll think about it and add more later. Nice start to your kit!