FWIW! I am put off the cloud for various reasons, preferring to use my own HDs which I back up. I am starting to use 2TB portable SSDs (Sandisk) and am just about to separate my library into two. One part is my historic images and I call this my 'archive' (obviously with backups). These are images that I will access infrequently. The other part has my more current images, say the last couple of years, kept on another portable SSD (this time more regularly backed up). My SSD's are formatted so that they can be read by either PC or Mac. If I then want to use more than one machine, as you do, it is just a case of taking the SSD with me. They are very small, come with connectors for both PC and Mac and Amazon sometimes has them on offer.
Does this appeal in any way?
Best wishes,
Jonathan