We once lived in an apartment that had the fuse box (and it was a fuse box) on the wall of the entry, not enclosed in a metal box or anything. It was visible from the most obvious place to put a sofa, so the woman who had lived there before us had covered a cardboard box with scraps of the living room wallpaper and hung it on the fuse box. An electrician who came to fix a different problem informed us that this was a no-no. So definitely check your local building codes; some of them is WEIRD.
Yes. I was speaking to the National Electrical Code, which applies almost everywhere in the States (though it has force of law only to the extent it is adopted/required by local jurisdictions), but local jurisdictions are perfectly free to have additional requirements. And of course the local inspector’s interpretation prevails.
It does strike me that if cutting power in a fire is the concern, the ideal would be to require an exterior main disconnect between the meter and the breaker panel, and to teach firemen how to yank the meter itself in cases where such was not present. If somebody rushes into a burning building and just hits the biggest breaker in the first box they see inside, that is not a guarantee that all power in the structure is cut. Lots of houses have two or more branch circuit breaker panels in different places.
Once upon a time, we used to pull meters from the socket. There were many injuries and “oopsies” from that action - wet gloves, distractions while pulling the meter glass (and not pulling is straight out), and leaving an open socket after the glass is pulled were too much for firefighters to deal with. Additionally, we can’t tell if pulling the meter actually shut the power off, there can be additional feeds or meters indoors that we don’t know about. Also, the service drop is still live, so you’ve only eliminated a portion of your problem.
Most departments 'round these parts just have the power company cut the power at the street, killing everything beyond. Much safer (and easier) that way.
I also believe that the breaker box can no be too high or too low.
No doubt. I’m impressed you can get them to respond fast enough to be relevant to a fire situation.
IIRC, the max height of the top breaker is 6’7" (2 meters). I don’t think the NEC specifies a minimum height but some places specify 4 feet. Clearance around the breaker box must be 30" x 36" x 6’7". Some states require 48" clearance in front instead of 36". Apparently the electricians are fatter in those states. 
I don’t have a copy of the NEC in front of me though so I may be mistaken.