Hi there! Hoping to tap this wonderful well of wife tips :)

What are some lunches could I pack that would be filling for an adult man with a very physically intense job? He works outside in the Texas sun all day. There are a few things I have to keep in mind though--he can't heat up any food on the job site and it can't be too heavy as he's concerned about feeling too laden. He's a hard gainer and eats a lot. I've been packing him 2-3 sandwiches, chips, fruit, nuts, and drinks (tea, juice, sports drinks) along with a gallon of ice water every day. Is there anything different you ladies suggest? Any other lunch staples that can last in a cooler all day? I've tried looking online but I find a lot of stuff he probably won't like--quinoa, salad and the like. He's a traditional meat and potatoes kinda guy. I don't mind making sandwiches for him every day but I'm sure he'd appreciate something new every now and then. The only thing I can think of would be wraps and maybe some different sandwich fillings like tuna or egg salad.

What do you ladies with hungry hungry husbands pack him for lunch? And thank you for looking!