Migrating existing World saves, including all of the player data contained within it, has been documented as being unstable and unreliable over the Alphas. SP saves data is stored in the Saves folder while SavesLocal generally keeps all the online server data for external servers you join. It really doesn't seem you are missing anything as that's just the way it is at times. Player Saves may become corrupted or reset. One method that has been proposed, that I could use successfully when migrating server hosts, was to strip the player back down to nothing. This means placing all inventory, toolbelt, and clothing/armor items in a crate before leaving the game and starting the transfer. I could do this in A21.1 when switching to a different server location. Upon joining the new location, the player save retained past level, skills, and other progression stats.
