Thursday's attempt on the Zinal Rothorn "Rotgrat" failed in bad weather - snow and ominous clouds, and very warm on the glacier approach.
On Friday, with bad weather forecast for the afternoon, we drove up the track to Bréona and climbed the Couronne de Bréona. This would be a 3 1/2 hour walk-in from La Forclaz, but the track is driveable - just! - to within an hour of the route. Park carefully and ask the farmer. You could also approach from Moiry dam. The ridge is loose to start, but soon becomes solid, with great knife-edge ridge scrambling and fantastic views.