I have made the appetizers listed below if I want to go healthy. You can modify them according to how healthy you want to make it.
Lettuce wraps - Freshly sliced veggies and grilled chicken. I use a healthy version of a dipping sauce by mixing vinegar with soy a finely chopped red or green chilli and some finely chopped scallions. If you don't care about calories than another sweet version of a dipping sauce would be good as well.
Grilled flank steak or chicken cubes marinated in ginger, garlic, lime juice, salt, black pepper and cilanto and served with a yogurt mint chutney (use low fat yogurt and blend it with some fresh mint, green chillies, garlic, lemon and cumin powder)
Salsas - Fresh tomatoes, red onions, garlic, chillies, cilantro and lime juice makes a delightful basic version or a fruit salsa with peaches, ripe pears, jicama, pineapple and mangoes with some diced red onions, dried chipotle chilli powder and a splash of orange and lime juice
Sandwiches - I make a version that is totally healthy. Make a mint and cilantro chutney in a blender (one bunch cilantro, 1 cup mint leaves, 3 cloves of garlic, 2 green chillies, salt and juice of 2 limes).
Thinly sliced cucumbers, boiled potatoes and tomatoes
a dash of ketchup
sandwich bread
Assemble by first spreading a thin layer of mint and cilantro chutney onto a slice of sandwich bread. Now place a few slices of the veggies. Take another slice of bread and smear a dash of ketchup on it. Place it on the veggies and cut into four. Serve several of them on a platter.