Ha! There's no pleasing everyone - good luck.
We tried a menu based around salads for a recent get together, which worked out great. We made all the food the day before and stored it in bags in the fridge so we could easily refill serving bowls as needed. We made
Jicima and grapefruit salad (just 2 ingredients),
Apple, carrot, and raisin salad (tossed in a little lemon juice),
Fruit salad with walnuts - lightly coated in yogurt,
Mediterranian salad with quinoa and bacon,
Black bean and mango salad (w/ onion, cilantro, lime),
Green garden salad.
We stayed away from pasta/ breads, mayonaise, added sugar, and meat (except the bacon) to include as many diets as possible with the salads. Grilled meat kabobs, a cheese/olive tray, bread basket, and a cheesecake rounded out the table.
I'd just focus on keeping it fresh - since that brings a quality to the table that is appreciated worldwide.
When I'm traveling, it's the exotic tastes that you never
experience at home that I love to try most... so just cook what you know best and trust your guests will be gracious and have adventurous palates.