Nothing wrong with downsizing. Sometimes your life or your goals take you in a new direction. Think of it as a new challenge or adventure and it can be fun. The trick is to think like a backpacker. Small tent or tarp/groundcloth. Light weight pad to sleep on. If you'll be somewhere with ample trees then sleep in a hammock. Super comfy, small, light weight. Backpacking stove & cook kit. No cooler, or small cooler. Get a dehydrator and start making your own meals. Small packable camp chair like a Helinox One, or Travelchair Joey. Get a good filter and filter water as you go if possible. Sawyer Squeeze or Sawyer Mini. I'll be doing 2-3 nighters with a 10 foot Mini-Cat or 13 ft. touring SOT kayak this summer, so I've been getting my UL gear together. I have learned a ton from the UL backpacking crowd about gear selection. You'll be fine on a 12 footer with some planning. Have fun!
"We are all visitors to this time, this place. We are just passing through. Our purpose here is to observe, to learn, to grow, to love....and then we return home."
Australian Aboriginal Proverb