In white water, I would die. I had to roll out once, when I got caught in a rapids (the first time I kayaked....). I got a bad cut and bled for a while, but I got it cleaned up and carried on once the deep cut had healed.
On a lake or river though, fish will let you drift right over them, til you paddle. You can observe really closely and nothing seems to get spooked but the ducks. Even loons will let you approach sometimes. It seems you're a floating log to them.
I know I'm a fish nerd, but being able to look at the wild growth of plants, and how fish interact with them is really a treat. A kayak will get you into beautiful places, and the birds, turtles and wildlife would be a great payoff for the paddling on their own. But the fish watching and habitat access is really something I appreciate. If I compare our lakes and streams to the ones I saw in Central Africa, there isn't a huge difference. A stream is a stream, and you can learn aquarium dynamics almost anywhere in the world.
The dragon flies are great too, once they come around. They land on the boat and you get to have a good look. Today though, I realized that a spider nest had hatched out in the kayak this Spring, and I had them crawling around annoyingly. I admit, some are sleeping with the fishes tonight.