I’am by no means an expert in this,but for the last few weeks I been messing around with mods so I might know something.
To disable buildings change city size in the world gen menu to 0, this should remove cites and most buildings, however specials such as the vault might stay along with stuff such like cabins.
You could use the no monster mods and the no wildlife mod to remove monsters.
I have no idea why you want to remove items but you could just blacklist every item.It’s worth a shot. Something like this http://smf.cataclysmdda.com/index.php?topic=11833.msg263763#msg263763.
Disclaimer:I have no idea whenever or not the above works and if they do the I don’t know about the unexpected side effects. Pls don’t sue me.
The problem is that a lot is hardcoded into the C++ source code of the game and can’t be disabled. You could try ripping out all the JSON and see what happens, though.