I'm glad to see someone else finds the FCPX tagging process eliminates the need for separate software to make clips. Back when Final Cut Express was a thing, I loved it but still needed to make clips to work with. The changes in the user interface with FCPX were extreme, but now that I've gotten used to working with it I love the tagging feature.

I normally have a rough idea of where I want to go with the vid and as I review the source I tag various 'clips' with keywords that are relevant either to specific lyrics in the music or to themes or motions, etc.