I love overnight Yak trips. Honestly one of my favorite ways to spend my time. All I have to say to you is ask yourself "do i really need this?" The experience is the whole trip so you want to balance things out. Bring enough so your not constantly hungry, cold, getting destroyed by bugs, or in serious danger in case of a medical emergency. With that said, you're also going on a KAYAK trip so make sure you have fun on the kayak too. There is nothing less fun than constantly bumping things in your kayak, having your legs crammed while paddling, losing things off the side of the boat, etc. Its really just trial and error but thats part of the fun! Hope you have great weather and a safe trip! TIGHT LINES!!