Yeah, the really hard climbs of MtVeeder are on the Sonoma side, and those are what I strive to be fit enough to ride. To begin and end a ride from home, down the steep side of Veeder, then up DryCreek and along Cavedale. That's one of the rides I look forward to getting in shape for. It would be about 20ish miles of pure brutal hillclimb/descent.
Another, my 'personal best' ride that I'm 'training' for from GroundZero is this : Down steep side of Veeder /over Oakville Grade/ across Oakville crossroad/ up SilveradoTrail to Howell Mtn/up into Popevly /over InkGrade/ across back PopeVly territory to the Monticello side/ and up and over Mt George/ back across valley to Veeder to home. I have no clue what the miles are for that loop, but maybe someone here knows.