I'm not celiac, but try to eat gluten-free most of the time. Gluten (or possibly wheat) gives my tummy such a hard time...
My biggest headache as a vegan is that so many of the snacks available in shops are sweet. I'm not too fond of sweet things and sometimes I just so crave salty and savoury stuff. Gluten-free store bought bread is expensive (and most of the time rather bad) so I bake for myself. Once every two weeks is enough (or less often if you have a big freezer
); I make lots of bread rolls and then I just grab one or two when I need to bring something to eat. Rice cakes are nice but not that nutritious. Carrots are also nice (and healthy) with peanut butter. There are plenty of spreads that you can have in place of nut butters - google for recipes or check what they have in the grocery shops in your area. Or just mash some avocado with a pinch of salt.
Soya yoghurts are handy and keep quite well even if not refrigerated. Have you tried adding hemp protein (or rice protein, eg) in place of too many beans for protein? I sometimes drink half a litre of flavoured soya milk for a snack - choc soy, eg.
When I eat nuts, I like to eat them with something - sundried tomatoes, eg, or peppers/tomatoes/lettuce/olives... gives a bit of moist and makes the snacks more varied. Chocolate is superb, too
You could get gluten-free sausages - eg. the kind that is packed so it keeps out of the fridge. They make great snacks, but are expensive.
Even if I don't have a lot of time to cook, I usually make large batches to have for several days. That increases food options a whole lot.