It depends if you are just watching your carbs, watching your carbs and also limiting your fat intake or if you are watching your carbs and are going all out on a diet.
Textures are important for snacks. You may for exampe miss toast and marmelade like mad. You may miss the crunch and the tangy hit. I used to eat a sesame rye crispbread from Lidl with a very thinly sliced mature cheddar and thinly sliced pickled onion. Cutting it thin was the key. The crispbread themselves are very thin and light. Much thinner than ryvita. It seems crispier and allows the seame seed flavour to come through better. I wanted to lsoe weight so I cut the cheese very thin. It works with this cripsbread. With ryvita, it would have to be thicker. If the cheese is thin, I have to cut the pickled onion thin, otherwise it over powers it. This way, I can probably have three of these for the equivalent of one ryvita with thickly cut cheese. Same crispbread also works for me with tomato flavoured sardine paste.
A big bag of frozen king prawns is good to hae in the freezer if you don't mind some easy cooking for your snack. Thawed and then marinaded in salt, pepper, chives and chilli, a quick fry and you have a great snack. If you marinade some spare ribs at the same time, you have salt and pepper spare ribs as well.
Often I can satisfy a craving for a snack with a drink. Cheap supermarket lemonade, the kind of zero calorie zero carb variety and which also appears to have zero lemons in it is transformed if you add the juice and soe yellow flesh from a freshly squeezed lemon. Make sure the lemonade is in the fridge so ou have a permanent supply of it ice cold. Mixed with just lemon juice, nothing else, it packs a bit tangy hit.
Also, I keep in some good quality picked gerkhins, olives stuffed tomatoes and my favourite hot wax chilli pepper. The Mezetta brand are reallly very very crunch and a million times better than any of their mushy supermarket equivalents.
Usually very sharp tastes with big hits and lots of crunch solve most snacky cravings.