I think pasta salad makes for any occasion of picnic, party or dinner. Just I try to keep it chilled whenever served and just keep adding to a bowl in an ice bath during the occasion. The biggest thing is what type of dressing to put over it....I go Parmesan Italian or Bacon Ranch most of the time, but occasionally try other dressings on sale at the market.
1 lb. cooked corkscrew pasta
1/2 cup each of finely chopped green peppers and sweet onions.
2 cucumbers that have been peeled, seeds scraped out, and chopped into 1/2 inch size chunks
1 to 1&1/2 cups of cherry tomatoes or similar small cut in half
3/4 to 1lb of small chunked up mozzarella cheese
1/2 cup shredded carrot
3 ribs celery that have been cleaned and chopped into small cubes
1 bottle of your favorite dressing (I get 16 ounces bottles and use about 8 ounces but have increased amount used at times)
Cook the pasta and drain but DO NOT RINSE. In a bowl put hot drained pasta and shake/pour a few ounces of the dressing over it, let stand about twenty minutes and cover and refrigerate (I do this night before affair and chop most of the other ingredients and store in refrig overnight too). Every few hours take bowl out of fridge and stir bowl contents, taste pasta and shake a little more dressing on it and stir). Return to fridge...this will help infuse the dressing taste into the pasta. Two hours before event take out bowl, stir past THEN add ALL the other veggies and cheese. Return to fridge covered, Before service take out and taste...the pasta should have the dressing flavor mostly and the veggies/cheese should retain their own flavor instead of everything tasting like dressing. You can sprinkle a little parmesan cheese over the bowl, stir once and sprinkle a little more. Either put out entire bowl in an iced service bath or just refresh from refrig when having small groups inside.
Side note: the addition of toasted chopped almonds, sunflower seeds, etc can also assist if you choose to use any. Just be carefull of those with nut allergies.