At that age, some of my dd's favorite on-the-go snacks were beans (cooked but still firm - we just rinsed them and threw them into a container cool or at room temp) -- black, pinto, lima, etc), corn, peas (frozen peas and carrots are still one of her faves), edamame (bonus with edamame: high in protein, fiber and iron!). She also liked freeze dried peas and corn, freeze dried fruit (although that was more a treat than everyday snack), sunflower seeds, whole-grain tortilla slices, lightly steamed veggies like broccoli (so they're not as hard as raw -- I'd just steam them and then refrigerate them until we needed a snack). Homemade chewy granola bars also started to be a hit at that age (more like fruit-nut bars, like Lara bars). Banana, zucchini, pumpkin bread spread with cream cheese (or plain if the cream cheese is too messy -- I used to put them into sandwich form for taking out of the house).
My son is big in to fruit and not very in to beans and grains. I just roll with it and try to give him bread or pasta at least twice a day and otherwise he is in to fruit/dairy.
I'd like to add (I apologize if I didn't see already):
bowtie pasta tossed with thick-grated parmesan or tiny cubed chicken or egg, etc
pieces of cheese (I buy cracker barrell's mild cheddar individually wrapped after much experimentation)
grapes sliced in half
cut up grilled cheese (is still good not hot too)
Cubed tomato with mozarella (my son will pick up an entire tomato and eat it like an apple)
obviously: strawberries and melons
blueberries are perfect and nutritious
fish sticks (haven't tried yet and kinda eeyew but wortha shot)
My son's day care fed the other babies cereal, crackers, or trail mix at snack times. While these are certainly less messy, I don't feel that processed foods are something to feed more than once a day or even week and they tend to be really high in sodium. But I will sometimes do a tuna salad squished between some crackers or bread. If you make the tuna salad and squish it really well into the bvread it's not messy.
I Love the idea of an egg slicer!
Egg tip: Unfortunately my son doesn't prefer boiled eggs: I got him into eggs by serving scrambled, gourmet style. I have to beat them really hard in a large bowl with a good whisk and add a tiny tiny amount of water just to get them to a foam-like stage then cook on very low heat with lots of butter and remove early to finish cooking on the plate. These are like butter clouds and even better with a tiny bit of cheese.
ETA: By processed foods I mean highly processed: I realize that some processed foods are good for bebe, like whole grain bread etc.