Another vote for the M6 (North).
The M5 does lead to the beauty of Cornwall etc, but it's very busy and there are often accidents and other jams
M6 North is a very easy motorway to travel on, and you can be in the beautiful Lake District in an hour, and then Scotland after that
Any that doesn't have loads of tossers clogging up the middle lane when there is nothing in the first lane. It is like a plague at the moment and I thought they were meant to be stopped/prosecuted for doing this