Having had three hard drives fail over the years I am a something of a backup zealot. These SD cards are three of the five we used on holiday, The portable HDD I use with the laptop so I can import the files into Lightroom on the desktop PC when we return home. After that the files are backed up to a local drive and to Backblaze.
Keeping tabs on the files works well enough - I just need to sort out importing them into Lightroom with all of the keywords and edits intact now :-) Just set the import running - 5860 files. Many of mine were done with exposure balance, (+1 0 -1 stop) so I had three for each to combine as HDR, so it's not quite as excessive as it might seem!