Wow! I was just talking about Campy cassette and the lack of the 12 (without losing the 26)! This year with the short little climbs the races have featured I've been needing the 26 so I'm running a 13-26. I think I preferred the second choice you offered, with the 21 in it. Up front I run a 46-38. I've been toying with the idea of using a 44. Maybe with a 12-26 it would be feasible. For cables I use anything, Jagwire, Weinman, or anything that's laying around. I don't even bother using Campy specific. I change cable often so cheap is good. In chains, for Campy, after much trial and error, I run Wipperman Connex (Campy spacing) I'll run the premium chain on the A bike, and stainless on the B. Campy chains, while good on the road bike are terrible on the cross bike. It's been my experience, and other's I've read. Any dirt, sand, or drop of mud sends them skipping. Let me know when you stock those 12-26, I'd be interested! Hope this is helpful.