...I like an idea of having several (3 or more) smaller safes or cabinets placed in different locations. Having one huge safe for everything (jewelry, documents, guns, ammo, etc...) sounds scary for me. If it is broken - everything lost. And huge safe can attract professionals, which can break anything.
Most home break-ins aren't done by a team of professionals burglars. That happens, to be sure, but it's typically targeted homes in the best neighborhoods, and a lot of those homes have pretty good security systems and many are in gated communities. The kills needed to get in and grab in those neighborhoods, and very speciialized.
For most of us, the culprits are one or two people looking to smash their way in, grab some things that can acquired and sold quickly, and get out. In that case, the big safe (hopefully fireproof) is truly SAFE, and the small safes, if they're reasonably well hidden, are best used to protect a single firearm kept there for when you're at home. With a little imagination, you can hide them in almost plain sight and it'll take time to find them. If you have a home security system hooked into local police and fire, the people doing the break-in are very sensitive to the time they've got to do what they want to do. A blaring alarm tends to accelerate them a bit.
In my home we do all of this. BIG and SMALL safes. It's not cheap, but neither is replacing any of the stuff stolen -- unless you have VERY GOOD insurance and your goods are well documented. I've got a medium-sized fireproof safe, and several smaller ones. If they find the small ones, they can carry the small gun safes away -- but they will get only one gun per safe. The big fireproof safe weighs 700 lbs. empty and getting it out of the house and into a truck is (because of where its kept) would be a bigger project, and I don't expect PROFESSIONAL SAFECRACKERS to be working in our neighborhood.
TVs are a quick grab, as are computers, and jewelry, and guns left in easily opened safes. Just look at what you see at a pawn shop to know what's sought. (The cheap metal gun cabinets you see at the BIG BOX stores
ARE easily opened with a crowbar.) I've got a number of iPads and several computers -- and they're not really theft proof. But as much as it would pain me lose them, I can replace them and continue. (You only have to have a hard drive fail, and find that your backup wasn't working, to realize that you CAN recover from a major PC loss.)