I am not knowledgeable about the English Brass Band tradition, but I like it when I come across it - especially pieces featuring the cornet or euphonium - instruments which do not occur in the modern symphony orchestra (although cornets were apparently used in Victorian English symphony orchestras instead of trumpets).
To focus on the cornet - it is like a trumpet in appearance, length, and basic pitch; but has a deeper mouthpiece and a conical bore (widening from the mouthpiece to the bell) which gives it greater sweetness of tone, and flexibility than a trumpet - at the cost of less sheer ringing brightness.
Early jazzmen such as Bix Beiderbecke and Louis Armstrong initially played the cornet but later switched to trumpet - which I personally regard as a step down into a more showily virtuoso style of soloing, characterized by extreme loud high notes (which the trumpet does better than the cornet).
The euphonium is the cello equivalent in a brass band and is like a smaller tuba - it has similar mellowness to the cello, but also a remarkable agility.
Both cornet and cello are capable of extreme virtuosity, as well as delicious sweetness, as displayed by James Shepherd who came from Newbiggin by the Sea (where my Father was born and where I spent nearly all my childhood holidays):
I would regard that as not just good but great musicianship. Even at its most extreme of high notes and fast playing, lyricism is always there - everything is phrased (and the cornet is particularly well suited to that, since the deeper shape of mouthpiece allows for greater control than with a trumpet).
And, for completeness, here is a euphonium being put through its paces:
Incidentally, the Black Dyke Mills Band (featured in the above links) were regarded as the London Symphony Orchestra of the Brass Band world. My Granny's cousin (also from Newbiggin) was invited to join, but could not take up the offer for family reasons.
(Black Dyke Mills was literally that - a Yorkshire mill for weaving wool - and the owners provided a paying job/ sinecure for its band members.)