Because it is my copporation, I would also have to pay the employer and employee NI contributions, and therefore dividends have always been the most tax efficie

Because it is my copporation, I would also have to pay the employer and employee NI contributions, and therefore dividends have always been the most tax efficient way for UK business owners to extract their profits. That said with these new corporation tax hikes, it's approximately the same now (dependent on the amount £££).