Gareth Bonello was enjoyable though as most of his songs were in Welsh, I found it difficult to fully engage.
I do wonder if it's a very English thing about struggling with music not sung in one's local tongue? In much of the rest of the world, foreign language music seems to be much more widely accepted (although obviously a lot more people have English as a second language to a much greater degree than is the situation with Welsh). Fwiw, one of my Top 5 bands of all time - Datblygu - were Welsh language. I also enjoy lots of other Cymraeg rock and folk.
Incidentally, I've got an extensive collection of MJ cassettes (albums, a few cassingles and some 'official bootlegs') which I'm trying to sell. If anybody collects these kinds of thing, do let me know.