I promised my oldest daughter more details on packing lunch and I've been procrastinating because this is a topic that is tougher than I thought it would be!
First, good containers make everything easier. We have some of the 4 tier melamine tifffins sold at Target this summer and those are good but...they're too big for daily use. They were OK for camp because I was also sending snacks but I think that just for one person's lunch they are simply too much. They also aren't going to look very 'professional' and my son-in-law is in a very status conscious industry. Having a couple of options also allows you to vary lunches so they don't get boring. I like the look of the stainless tiffins,carrying cases, and reusable bamboo utensils at Happy Tiffin
A laptop lunch set in a dark neutral color could be good:
and Bento boxes come in a variety of sizes, shapes, and colors. Zojirushi even makes a "Mr Bento" line for guys who don't want to go to work with Hello Kitty or Spiderman
Since packing a lunch has become more mainstream and less 'blue collar' more options have appeared. Once you have a few good containers (and smaller containers and thermos-type things for hot items) then you can tackle the issues of keeping foods at their most appealing temperatures and creating an appropriate, attractive, and enjoyable menu.
Temperature: Currently in the school supply sections of both Walmart and Target I've seen little mats with cubes of blue freezer coolant fluid that you could (carefully!) cut to fit your containers. Hardware and building supply stores sell a very thin silver insulation product that can also be cut to fit to line or surround containers.Tiles from the building supply store can be heated in the oven and packed with the lunch to keep things warm (not a concern in a Chicago summer, I know- but winter comes eventually). Some foods handle being frozen and serve as natural ice packs. Yogurt does very well and lunch meats and cheeses often do too. For a wrap or a sandwich you would freeze the meat and cheese then pack it separately from the veggies, condiments and bread.
Menu choices: Google bento, low carb bento, and low carb lunch ideas. There so, so many options. With someone who isn't excited about raw carrots and celery, think of ways to put the veggies in the food. Shred them and put them in things. It doesn't matter how good for a person something is- if they don't like it and there are other choices (Hunny Bunnies, Lara Bars, vending machines!) the more desirable thing will be chosen. Rice is nice because it is versatile, freezes well, and its so easy. For a guy who likes to graze all day, small rice balls (onigiri) can be filled with things that are good for him and yummy- take those veggies, mix with some meat and terryaki for instance. Thai spring rolls can be made without the rice noodles and using butter lettuce for a wrapper with no loss of taste. Steamed chicken and veggies with some soy sauce on a bed of rice is calorie conscious and more attractive than the raw carrots. Burritos and tortillas are good. For people who already spend half the GDP of Zimbabwe at Whole Paycheck, why not use some of their healthier hot bar items in a thermos? A tiffin would be great for a big chef's salad but guys usually don't feel that they have had a full meal with a salad as a main course. When the weather turns, chili or stew in a thermos is filling and comforting and an easy way to get veggies in someone. Hard boiled eggs pack well and are loaded with protein. Bagels with smoked salmon and cream cheese are another option.