You might want to look into getting a food dehydrator. It can help you with making great snacks for your family. My family loves it: fruit roll-ups (you can just puree fruit and don't have to worry about adding sugar. it is sweet enough), apple chips (my girls are eating them right now), beef jerky, veggie chips, etc. So many great snacks that last a long time and don't need to be refrig. Would be great for boating, camping, outdoor activities. You can also make fruit roll-ups without a dehdyrator. You can do it in your stove, just google "making fruit roll-ups." sometimes you can also find recipes under "fruit leather." Sometimes I grind flax seed (or any type of nut or seed) and mix it into the fruit puree. Adds protein and healthy fats into their diet.
Also, I can get my little ones to eat carrot sticks if they have something to dip it in: guacomola or hummus. Both so easy to make yourself. but might be a little mess for the boat. guess it depends on the type of eater he is!
You can also find healthy hot dogs. Applegate, Boar's Head, or Shilton's makes healthy hot dogs. no nitrates, no perservatives, etc. My girls actually prefer these over the "traditional" hot dogs you buy.
You can try making your own chicken nuggets. use chicken breast (dice up), dip in a sweet potatoe puree, then roll in whole grain bread crumbs with spices of your choice. You can bake or pan fry. I pan fry in a healthy oil. I make a whole bunch at a time. Then I freeze the leftovers. I take a few out at a time and reheat in the toast oven. The whole family enjoys them.
Does he like pickles? I'm so surprised but my very picky-eater 2.5 year old love old-fashioned kraut (fermented which has the healthy live bacteria like yogurt has). Not sure if you can buy it in your area, but easy to make. I add dill to it to taste like pickles. My daughter calls it her "special pickles" and wants to eat it at every meal (seriously every meal. even with her pancakes!). She is eating a veggie and healthy digestive bacteria. Doesn't make her gassy like the jarred kraut you find in the grocery stores. You can google on how to make your own kraut or fermented vegetables. Easy finger food for them. My other daughter loves fermented beets or cooked beets!
Just try things that you might think "there is no way my 14 month old will like that!" I've been surprised on foods they like, even if it isn't something I like.