FolderSync works well for keeping the Amiga in sync with the NAS, where it can be backed up. This is fine if the character set and Amiga filesystem attributes being lost isn't going to cause any problems.
The other thing I like to do is create an ISO with the files on. If you ensure it is created with all the Amiga extensions then you won't lose anything, and it can be mounted and files read easily on any system. This is similar to the LhA solution but it's less hassle to get to individual files.
