Some good ideas. I agree that keeping it light is best. Lettuce wrap/cups can make a great presentation & easy finger-food. A few we've done with pizza:
italian - arugula, mushroom, italian parsley, pear, fresh lemon juice, olive oil (optional - blue/romano/asiago cheese, crushed walnuts, diced tomato)
spanish/mexican - cilantro, jicama, green chiles, red onion, fresh lime juice, olive oil (optional - cotija or manchego cheese; chile powder/mexican oregano/paprika for seasoning)
greek/mediterranean - english cucumber, red onion, green melon, feta cheese, mint, dill, fresh lemon/lime juice (optional - olive oil)
grill some veggies (mushroom, squash, zucchini, onion, eggplant, tomato, kernel corn, carrots, baby turnips, green beans, etc), drizzle with balsamic & parmesan cheese
Chop the ingredients & serve in baby romaine or radichio leaves. For larger amounts, wrap in lettuce, romaine, or cabbage leaves. Tie each section closed with cilantro/parsley stems & cut to size.