Yeah, one gets to know ones limits re: alcohol. I could imagine a few hours of careful wine tasting (I usually split tastes with a friend and spit liberally) and take home bottles I like and a couple hours to sober up. And, getting full tasters at the breweries and not drinking more than a sip of each - best with more friends. But that’s me, and I have a good drinking/travel companion so am rarely actually alone, and I’ve lived and drank in oakland alot so it’s not foreign (as you can tell from my writeup 
). If you’re not going to drink at all, there are some fun eats as mentioned - I would focus on the places I think are oakland specific, like Chicken and Waffles and E&J and a hoof through chinatown for buns and maybe chop house if the menu seems cool or one of the water-facing places like Forge or the places on either side which have great atmosphere and good food but won’t actually knock your socks off.
Berkeley’s options (especially vik’s if one hasn’t been) rise in comparison. I don’t know if you mentioned an easy path to fruitvale - I forget where the capitol corridor goes through there - fruitvale has all the tacos.
