Dress for the environment. Which doesn't mean, you have to spend a lot of money on gear. My current favorite paddling jacket also happens to be the jacket I use hiking in the rain. I like eVent because it breaths really well, but you can use Gore tex or anything else you like. It also means synthetic base layers when needed. It may also mean A light colored UPF shirt. It means wear what is appropriate, and be prepared for the environment. Adapt accordingly. It also doesn't mean you have to dress for submersion. while I think this is safer, many people can't afford to dress for submersion. So if the water is 50º and you are going paddling - and you should, no one else is out, and the world is beautiful and quiet! - pack dry, warm clothes in a dry bag in case you get wet. Maybe even a stove for a hot drink!