A few minor questions that are stuck in my mind

Re the SD card… This is the thread that was also in the back of my mind… I don’t fully understand the answer so I guess my question would be does the SD card become ‘internal storage’ and make my music database (?) move that bit quicker?

The OP had 3,000 movies and posters taking up 4Gb of space…

The answer by nabsltd was:

The space that is being taken up on the Vero is by the cache of the artwork. The cache is not a direct copy of the image files, but are scaled-down version. You can’t get rid of it, since it will just re-populate with the images. It can technically be moved off of internal storage, but that will likely make it slower.

Unless you are completely out of space on the Vero local storage, the cache is not going to cause slowdowns of any kind, especially when playing videos. The size of your database could be an issue, depending on what kind it is (Kodi built-in or MySQL), where it is stored (on the Vero 4K or on a different machine), and what skin you use.