Very interesting.

I actually really like the festoon lights! Fairy lights remind me too much of Christmas to have as an all year round feature.

Pendant light choice would usually be for a specific purpose so if you will move things around I would have a rethink. It may be possible to have a pendant with a long lead & hooks for the cord that would allow you to move it within a reasonable distance of the connection point. Maybe some general lighting might work better e.g. or two or three directional spotlights along edges or the ridge line & on dimmers if possible. Subtle strip lighting at the top of the grey wall & the addition of a feature decorative wall hanging & potted plants would look nice too.

If you are using LEDs always choose warm white for domestic interiors.