Well, I actually like to take something like Boston lettuce, or butter lettuce, and use the leaves as the "bread" to make a sandwich. I wrap the lettuce leaf around whatever I am eating - could be turkey, cheese, onion, drizzled with a bit of balsamic - it could be a bunch of finely diced veggies, again drizzled with some balsamic - even some olive oil too.
I much prefer a homemade dressing to a store-bought. Just a simple 1 part balsamic, 3 parts good olive oil, salt, pepper, oregano, pinch of sugar and stick in blender to emulsify. It's really refreshing. You can do the same thing using a bit of lemon juice and a big pinch of dry mustard for a different flavor.
Whole, unsalted almonds are VERY healthy
Water packed mozzarella is good
spinach and arugula make a great salad mix
spring onions
roasted red peppers
or goat cheese
It's always good to have some protein in a salad too - it's more balanced. You can top one with a bit of fresh salmon or canned, fresh tuna, or canned, chicken chunks, whatever. Don't forget a bit of grated cheese - it's still a dairy.
If you have to pack a few things in separate containers so they don't get soggy it will make your lunch more enjoyable.
I'm rambling but I'm really tired. I'm sure I'll find my way back to this thread tomorrow.