1)You can get things done: When my (canadian) wife had to get a bank account in england, they almost reduced her to tears, refusing to do anything until she got documents she couldnt get. In canada all i had to do was ask.
2) no nannying: in england recently a fence was put up around a pear tree so people wouldn't get hit on the head by falling pears. In edmonton there is a giant bridge across a giant river with a 3 foot high fence on it. I assume the attitude is that if you are dumb enough to jump off a bridge, it's not our job to stop you. This is very refreshing. It also weeds out the lunatics.
3) the weather. I love the snow and the nice dry cold.
4) the inclusiveness of the culture. from newfies to inuits and first nations. being a canadian seems to me to mean being aware of the existance of other cultures. Some english people don't even understand that things might be different elsewhere
5) the size. Canada is giant and this results in a wonderful emptiness. Overcrowding in the Uk is causing some serious social problems. this is true of many places but definately not in canada.