For a group that size it is hard to beat the R&G Lounge in Chinatown. Everyone gets the deep fried salt and pepper crab at least once. Had a few large group gatherings there and always good, lively and fun.
Then go down the street to Li Po Cocktail lounge for their Mai Tai and to hang out. Fun, diverse crowd.
If you hit these two places in one night you will have a good time, good food, good drinks and see a fun side of SF missed by many.