After much deliberation, I went with Embossed Leaves Socks by Mona Schmidt, which were featured in Interweave Knits Winter 2005.
I wanted something with enough pattern to keep my interest, but my last attempt at cable socks nearly did my head in! This pattern has an easy repeat, and I love the way the leaves "fall" into the toe.
It also uses a tubular cast-on I'm not familiar with, so looking forward to that challenge!
Now I'm off to choose wool - I'm thinking a subtle variegated? Any comments/thoughts? I'd love to hear from anyone who's already knitted this pattern.