> a good starting point is to split photos into groups/folders with each
> group fitting on a screen
and in Plasma Active you do that with tags.
which is even faster because you don't need to navigate back and forth, create a folder that shows along side files and then drag files things to it in the same view ... you just drag to an existing tag (or on to "new tag").
you can tag things with multiple tags. many of the photos probably have metadata put their by the camera. there are also tags the system can infer such as "mark all these photos as related to this activity".
when viewing, you select a relevant tag set (which can be 1 or more) and optionally a time slice.
so you get all the organizational power of folders without the drudgery of the folder UI or the limitations of single entry hierarchies.