So right now i agree the save system does need some more work and i will be looking in to that, It works fine for single player but multiplayer is another thing altogether. Unreal’s build in save system just inst that great for multiplayer and definitely isn’t designed for large scale multiplayer most solutions involve C++ systems and other external data base programs. If you want to continue using the build in system your idea for create individual saves for each player (Then rewiting that save when the player leaves and dies) is a good idea for making the best out of the built in system. When i have some free time to come back to this project I will take a look at trying to implement something like that to improve the pack.
But as i said if your looking to have a much more robust system you will definitely need to look at more advanced ways of saving and managing the save data out side the engine.
I hope that helps