Hm, I think this is one of those things that you figure out as you go. So for Atomic Blonde, that movie is huge on stylistic colored lighting, and the protagonist wears a bunch of different wigs throughout the movie, so I always note that, but I wouldn’t necessarily for another source. I also love to emphasize movement and make dance-like vids so I always record direction of movement, where another vidder might not. A typical keyword string (which I just punch in as the name of the clip, although I know some people use the metadata fields in Premiere) might look like:

Lorraine walks toward camera sunglasses blonde in hallway with strip lights green

Percival punches cop left to right then flips him in front of car headlights fight alley night wide shot

Pan across city skyline superspeed exterior night

So I don’t hit every one of those categories for every shot, just the relevant ones, and I by no means try to be comprehensive! It’s more like, what am I noticing most about this shot, and I jot those things down because later on I might need to find more night shots, or close-ups, or fight scenes. And you’ll figure out as you go what aspects of the source are interesting to you, and tag those more thoroughly (Hannibal has a bunch of disturbing nature images so I always tagged those with ‘nature’ and the murder art pieces with ‘murder’). Make sense?