If the weather holds up and you wanna enjoy good ocean view and good dining, check out Cliff House. Dining is downstairs. Gets windy/foggy at night, so layer up.
Awesome, quality chinese food can be found at R&G Lounge in Chinatown. Expect to wait an hr or so on weekend. Or if you want something more on the chill side, check out Mission Chinese food in the Mission.
Hit up Suppenkuche if you want delicious German brats/beer. Tommaso's if you want the best lasagna IMO. Clementine's if you want to bring a date for French cuisine.
Legion of Honor - beautiful exhibits and architecture, de Young, MOMA, Palace of Fine Arts - all good places if you have time.
Honestly, if you've been to SF before, skip the Pier and GGB. Depending on what you think is a good time out, there are many less "cliche" attractions in the city.
Good luck and have fun!