Pork scratchings are my guilty pleasure for a crisp replacement. All fat and protein and no carbs. Similarly salami/pepperoni crisps. Thin slices of cured meat, placed on kitchen paper in the microwave and zapped for about a minute. Best covered with another sheet of kitchen paper or a splatter guard.
I have to be careful with nuts, particularly peanuts being a legume, as my has the ability to break them down into glucose more efficiently than some other people. I am the same with beans and lentils. They seem to have almost twice the carb content they are supposed to have as far as my digestive system is concerned and I know some other people have the same reaction. Portion control is very important for me with nuts.... and difficult to enforce as they are so moreish.... Plus I buy large bags both to reduce packaging and because it is more economic. Plus, I usually end up having to inject insulin for nuts.