Update - Disconnects and Latency Issues

I'm not saying to make it so it saves every second, but honestly thats one of the two ways to even stop duping in general. That+item IDs

They already have item IDs. They're not using them.

Every one of those saves uses enormous resources.

Not actually true.
It doesn't have to save every second either, just every transaction, and it needs to handle every transaction as a discrete unit, not individual parts that can be interrupted.

If it did that it wouldn't have to save every second, or every transaction, it could save on quit and not risk duping anything, it'd just risk data loss, not data duplication. That's the entire point of ACID design.