The development team is working on save timings, where the worlds will save quicker, better and more efficiently. For the meantime, you just gotta make sure that you are doing /save-all every so often,
if you have a skript, this might be useful.
every 5 minutes: #depending on how often you want it to save, 5m is good.
console command "save-all"
send "Saving server" to all players where [input has permission "sk.saves"] #this is just to notify when it happens. You can change this, but it will send to all players that have the "sk.saves" perm.