Fellowship of Humanity

Check out the Humanist Hall on 27th St. in Oakland's Uptown area.  It's an older but charming building with lots of windows, a stage, and a kitchen, and it does have a decent-sized outdoor area as well.  They allow you to bring your own food + drink, and they are very reasonably priced.  I had my 50th b-day there and it was wonderful.  Because it's very DIY, you can decorate as you like, so I think it would be great for a sweet 16 party as well.