If you avoid bulk and expense for warmth and shelter, you will depend on your fire and your field improvised shelter, which can work just fine.
Be sure you have a good fleece or wool sweater (worn underneath your kayak shell, which i assume you have). See if you can fit in a heetsheets bivy bag and a balaclava helmet or watch cap along with gloves. Since you will be around a fire, wool might work better than fleece, although I personally prefer fleece.
Too much wool on your body when in the water can be dangerous
as it weighs you down. Nearly lost a scoutmaster one winter while canoeing.
He was a big fan of Filson clothes.
Also I've noticed
how much lower in the water others have floated when wearing
wool clothes after falling out of a raft. Makes it harder to
see obstacles downstream and to catch your breath.
Sure, you may get some holes in your fleece from a campfire, but it will dry faster anyway. In a survival situation, the last
thing I would worry about is how snappy my clothes looked.
I like the polypro heavyweight army longjohns for boating
as they are the lightest to carry, the fastest drying, and
add to buoyancy.