I prefer having more light in the morning, but I'm a morning person. My feeling is that driving is safer in the morning in daylight, as people are half asleep at the best of times anyway. I have no studies to back that up, it's just a feeling.

I couldn't see the UK changing to be on the same time as central Europe. It just seems like a very un-British thing to do, for better or worse. Portugal is on the same time as Britain, and so are the Canaries, so it's not 100% accurate to say Spain is on CET time.