Well, until you said there would be 20-30 people, I was going to suggest a tea party. I just LOVE tea parties!!! I host them from time to time, but I haven't hosted one for more than 12 people. The food can all be made in advance - scones w/butter and jam, finger sandwiches (cucumber, egg salad, and chicken salad), tomato & bacon salad, and then assorted pastries & cookies (I usually get the frozen cream puffs and make sugar cookies). It's a lot of prep work, but them you can definitely sit down and enjoy your company rather than be fixing lots of food. You might still want to consider it. I can provide recipes if you're interested. Just PM me. Good luck!