If you're going to a park or campground for your picnic feast, you may be able to bring or score a grill. A hot picnic entree like classic grilled burgers, brats or chicken adds a new dimension to a simple basket meal. Just remember to avoid cross contamination with your greens, and keep your raw meat on ice. Oh, and don't forget the condiments.
If you think coming up with a grill and charcoal might be a hassle, try investing in a disposable grilling kit. You'll get all the stuff in one convenient package.