Packed Lunch Suggestions for 2 Y Old

Tortilla wraps/cold burritos: veggies, sliced cheese
Sauteed tofu cubes: Saute them up in olive oil. You can include dipping sauce if you want, but my son gobbles them up
The usual sandwiches: PB and J or PB and sliced apples or bananas. Veggies, cheese (we don't eat meat, but of course sub in here what you want!)
A high protein greek yogurt with fruit and cut up veggies and a slice of homemade bread is nutritionally on par with a main dish, so you could do nutritionally dense snacks in lieu of a main dish. He may be more apt to eat that.

My son is almost 3 and eats so well when he's allowed to snack. When we call it "dinner" he won't eat it. But, handfuls of things or bite size entertaining foods go over great! :)

My kids have alwys loved Lunchables, anything from Turkey, Ham, Nachos, and Pizza, I think they even have hamburgers now which just sounds disgusting to me. They are convienent and they like them. Toddlers love finger food too so its perfect.
Or take the same old PB & J and cut it into shapes, making the old, new again!

my son likes chili with tortilla chips for dipping and shredded cheese. (turkey chili, baked chips, low fat cheese)

Cous Cous, chicken and veggie in one bowl mixed.

I usually like to just pack whatever is left over from dinner the night before so maybe plan your dinner meals with that mind...

My son loves anything with italian dressing on it, so often, if we need a 'picnic type' lunch, we pack tuna, cucumber, and/or pasta salad with olives and small chunks of meat, all with italian dressing on top. He always likes a pickle or two and maybe string cheese too. Add some crackers and a couple toddler cookies and he is set.

I like the idea of using cookie cutters for sandwiches. What a fun surprise. You could also make your own lunchables and get litle cookie cutters and cut the cheese and meat into shapes, add your own saltines.

Does your toddler eat chicken salad? My son likes it (I do hard boiled egg, chicken, a little mayo, celery, lots of pickle, a little pickle juice for moisture and flavor, some black olive). It's a good protein and he can it it with a fork with crackers or chips on the side.

I have done homemade soup, even mac & cheese in the bowl shaped thermos. Turkey rolled up with cheese cubes, celery and carrot sticks along with some yogurt (which when my kids were that age, they thought was vanilla pudding LOL!) I also used my bigger cookie cutters and would use them to their cuts wheat/ whole grain bread and then make sandwiches, so when they opened their lunchbox, each day was a different shaped or character. The teacher even suggested that to other parents of picky eaters, and apparently the novelty helped them pick up their sandwich and eat lunch! Good Luck!