Your list is excellent and very similar to checklists I have in my garage to help me remember to bring what I need. I actually have two checklists, one for each of my kayaks because the ancillary items needed for each differ.
Two things not mentioned on your list that I carry are:
Tools -- I bring two small screwdrivers and a small adjustable crescent wrench. I keep them in my boats. Both of my boats have a number of screws and bolts and in the case of my Mirage Drive a variety of moving parts that may need on-site tightening or repair. My tools have indeed come in handy -- once to reattach a Mirage Drive fin and once to adjust my rudder.
Backup Ratchet Straps -- I use ratchet straps to car-top my boats. I carry an extra set in my van as a backup. On one occasion I had to use a backup strap. The rear strap on my boat failed at some point on a trip from my house in Pasadena to Jonas Green. I didn't know it until I got to the park but I recall hearing a thump while I was departing my neighborhood. I stopped and checked and didn't notice anything amiss. But I suspect the strap started to fail at that point. Interestingly I drove the route, approximately 15 miles at times at 55 mph with only the front strap firmly holding my Revo in place.
Olive Hobie Revo 13
Hidden Oak Native Ultimate 12
Author: The Simple Joys of Kayak Fishing (Tips and Tales From an Old Guy in His Plastic Boat)
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