Here's some ideas for passed appetizers for the summer months.
Grilled shrimp with an herb vinagrette dipping sauce
Mini crab cakes
Prosciutto and Guyere pinwheels
I made this up yesterday for a get together based on things I had on hand and they were very popular and colorfull.
I created a mango avocado salsa by dicing mango, avocado, and red bell pepper very finely. I added some smoked salt, lime juice and olive oil and some hot sauce to taste. I seasoned some shrimp with cumin, chili powder, salt, and a little coconut oil and then quickly grilled. The shrimp were large so I sliced them in half lengthwise. I put belgien endive leaves on a cold platter and spread some salsa in each and then topped with one of the shrimp.
For mains, grilled butterflied leg of lamb is nice. I also like roasted halibut for summer dinner parties.