I watched the pilot again this week, and for the first time, really enjoyed it. Except - I've never been keen on Blamire, however I now realise why this might be.
Who says (unless Roy Clarke has actually said it) that all the characters have to be likeable? One of the driving factors in comedy and drama is conflict, and how it is dealt with. It is not unusual to have "unpleasant" characters in tv and films.
Blamire had grown up with Clegg and Compo, his and Clegg's family might have had more financial stability than Compo's, but they were together when scabby knees were part of the school uniform. Blamire developed his airs and graces and now berates Compo, despite his disadvantaged start in life. So Blamire is a definitive counterpoint to Compo, and has character traits that make him less likable.
Incidentally, I really like the way Roy Clarke wrote Compo so that he often took no notice of Blamire, and didn't let the arrogant sniping diminish his playful childishness.