I can't entirely agree with you. I say the 2nd Amendment not only protects the people's ability to overthrow a tyrannical government, but it also recognizes and strengthens the individual citizen's God-given right of self-defense -- a right that pre-dated the U. S. Constitution.
Therefore, in my opinion, and in addtion to the other aspects of its original understanding, A-2 most certainly IS about crooks and burglars and bears -- and even those hostile "Indians" mentioned by Justice Kennedy during oral argument.
Nothing preys upon man more then fellow men. Crooks and burglars are just unorganized predators. Government is a organized predators with wood pulp paperwork back up the killing and thieving.