If you correctly match the carbs to the cereal you shouldn't hypo.
Try fruit juice as a hypo treatment if you don't want sweets/coke etc
You could try snacking on fruit or berries. 60g blueberries is 9g carb. I sometimes have them to pick at when I'm at my desk other fruit requires insulin, but it is a healthy alternative to other snack options
Cheese is basically no carb. Or a few nuts but not too many!
Hi. Nuts are good and I agree your insulin may need reducing a bit to avoid hypos with lower carbs. Don't worry too much about fats; there is a lot of discussion currently in the media about the origins of the 'low-fat' fashion and the fact that it was based on bad data. Just keep the fats unsaturated where you can e.g. fish, omega 3 etc.