There's something special about winter paddeling. If properly planned, equipped and skilled, I have absolutely no qualms about a full day (and even evenings out on a full moon) concerning enjoying an invigorating safe paddle. - even solo.
Remember, in any of life's activities, there is always the necessity for honest and complete risk management. A wise and prudent participant alway evaluates and plans ahead keeping in mind: 1 - The man -YOU! This means your health, fitness, conditioning and survival skills;
2 -the machine (your boat and its equipment); 3 - the environment (sea conditions, weather, proximity to refuge spots).