I also like how his songwriting matured too. I think about the songs on "Lightfoot!" and then I listen to, say, the Cold on the Shoulder album, and my, his voice and songs develop over time very nicely!
Am I the only one who thinks that, say, Cold On The Shoulder is almost, if not equally rich, as the Shadows album?
Pardon my fixation on Cold on the Shoulder

but I think that's one of his finest albums, let alone Shadows...