you can backup any files you choose into a backup file on the pc with the program, Bob. That backup can be in arranged in folder or alpha order, keeping the file structure or using all adjacent spaces and set to the size of a specific card. Smaller backups can be effectively merged as I describe in another post.
The features you miss were never provided with a previous keyboard, Bob, they came with an expensive add-on hard disk, and then with further expenditure on a techmanager program which was used by a very small minority of owners. I don't recall any indication anywhere that all of these features would be provided once the product and software had actually been seen. The favorites are now 40 banks of 9 songs each for each SD card, this apes the custom load lists for your gigs. Midis have 99 editable playlists, each with a possible 99 songs from a max of 999 songs. Audio playlists too through the card reader. SD works with long file names that can be loaded, saved, backed up, restored and merged into new backups, and you have alpha sort and load by number already built in. As you have said yourself, once you have your songs on SD the problems are mainly over. The difference is in relative extra expenditure compared to the hard disk/techmanager. We have one free program which helps hx backup people hugely. Let's see if something else turns up...