Something all of us should consider is having what I call for lack of a better term, a "self defense system" that is "Brain Centric" rather than "specific tool" centric.
There has been much effort nationwide on gun laws to make the laws/rules on carrying guns more straightforward and on statewide levels, relatively uniform throughout a state. Many states have "Pre emption".
On arms other than guns however, things can go sideways, especially with edged arms and/or martial arts type arms.
Biggest problem I see is that many states don't have statewide pre emption, so even if you are in compliance with state law, you could unknowingly be violated some country or city ordinance.
I reside in California and statewide laws on knives for example aren't too horrible, but where you get into trouble is in the local areas.
And then of course they have laws on the statewide level against many items and on some items, the law is "gray" and subject to interpretation. Penalties for violating many of these laws is a "Felony" btw, so they can really cause you nightmare legal problems.
Fortunately for me I reside in a county where my sheriff does issue CCW permits, yes there are probably 100k plus of us in the PRK.(People's Republic of Kalifornia). FWIW, permit is valid statewide, even in San Francisco and Los Angeles.
Right now because of the way laws are here in Cali, the only self defense tools I will carry are my pistols.
Ideally an ASP barton or nunchucks would be what I would like to carry in addition to my pistols.
Other items I would like would be certain edged arms.