You're correct about what meals you'd be missing. If the southbound is running late, however, you would get breakfast before Sacramento.

On the northbound trip, the wine tasting is scheduled so that it's finished before the Portland stop, so don't worry about that. (If you've never taken the Coast Starlight before: don't expect something too elaborate and informative, since the Parlour Car attendants aren't necessarily wine experts, but the wine tasting does make for a nice, unique "social hour" in the afternoon.)