My own experience of the northern railway network is as follows.
Short journeys give mixed results. I travel from Castleford to Leeds in less than 20 minutes, I prefer this to going by car, generally the train has ample seating and runs on time, all good. This changes dramatically if you do the same journey for work, I spent 2 weeks doing this about 5 year ago, you never got a seat, it really was ‘packed’, sometimes you couldn’t even get on the train, you then had a 30 minute wait until the next one. At the time I bumped into an old school friend who had worked in Leeds for 20+ years, who said he had given up on doing petitions for extra carriages and just had to live with it!
So, short journeys, depending on time can be either very good or very bad.
Longer journeys are SLOW, it takes as long to get to Liverpool as it does to get to London, which is around 100 miles further. The journey to Liverpool is very tedious, never really gets going, lots of stop/start and slower speeds.
As said further up the thread, the north needs a high speed line between Liverpool and Hull, with Leeds and Manchester as the other stops.