That makes no sense, why would you drop by a thread about making a gun vault, then roll your eyes about someone discussing theft? Isn't the reasons we have gun safes to prevent fire damage and theft? Whether I live in a low crime area or not, I think it warrants discussion, on a thread that is for discussing a gun vault. That's not paranoia it's just common sense.
Most thieves are not going to chop through floors, batter their way through concrete walls, or anything else that require specialized tools and time to use them. They want in, grab what they can, and get out, quick!
Thus my suggestion of getting a good home security system, If they take the time to start chopping through walls or floors, the cops will be waiting for them.
If they have the time to work, and the experience and tools to do so, no home built, jury rigged "vault" will stand up to a determined attack. Heck, given time and tools, no expensive, properly engineered, concrete and steel vault will stand up to a determined assault. The trick is to make it difficult and time consuming to break in, not impossible.
I am a big fan of Liberty safes, but they can be broken into with common power tools. Specifically, hand held metal cut off tools. It is just going to take a lot of time!
I am not disparaging your efforts at making your guns safe, just trying to interject some reality to you efforts.
You stated in your original post, that you weren't worried about break ins, yet you seem to be willing to expend an awful amount of effort to defeat an unlikely event.
So why go to that much trouble? Put a good strong steel security door on the room, maybe do something about fireproofing the ceiling, get a good alarm and security system, and call it good.
Now if you want to go all out, and spend the money, have reinforced concrete walls poured and get a vault door like Liberty safes sells, and set up a room like this...