Hi Nicole,
I make little muffins and burgers for luke and freeze them, and then they only need to be heated up in the microwave for about 30 seconds to be served. These are always loaded with veggies and then ground turkey/chicken etc. Homemade fish fingers are good too, or croquettes.
You could also do small whole grain pitas, cut a little bit at the top, then add grated veggies, cheese and a little diced meat and ask DCP to warm in micro for a minute for cheese to melt.
Little pre-cooked potato cubes that can go with some little veggies and cubed meat might also be a nice change instead of a bread meal?
FWIW - our day care provides the food, we don't bring it, and lunch is sandwiches with various spreads and fruit day in, day out. What you're doing now sounds better than what they are getting!