Well, I've done three of them... Hornli - good, easy and crowded. Lion - better than Hornli, a little more difficult but less crowded. Zmutt - much better, harder and far more serious, but you'll probably be alone, not much fixed gear, come down the Hornli. Ignore folk who say it's a choss pile... It's the most esthetic choss pile in the world!
Don't overlook the Wetterstein in Germany/Austria! I just remembered a great climb tha I did in 1963: the Zwoelferkante on Die Zwoelferkopf, a subsidiary peak on the Waxenstein. It's an Alpine IV+, with some decent but pretty runnout climbing at the 5.7 level. I can't really remember much about it, other than it was fun and a lot harder than I was expecting.
I recently bought the book "Mont Blanc Supercracks" since I planned to go to the Alps and climb some cracks. [ Impaler in above posts expected this book to be good].
This is the worst climbing book I've ever used- basically garbage with nice colored photos, bad topo and zero information about root quality , approach and decent