I agree with much of what you said, only I don’t think of rolling chords as more delicate. For example, the Faure Impromptu, as you mention, with the chords all rolled can be as rich and powerful as the ocean, depending on your crescendo. I was taught to play the opening chords of the Debussy Danses with the left hand broken and the right hand unbroken. I wouldn’t do it in the Faure. Now in the Interlude from the Ceremony of Carols it is not necessarily clear what Britten wants unless you listen to Osian Ellis. It is also a question of how much liberty you want to take in a situation where you more-or-less know the intent of the composer.
I have found that since I began working on arpeggiating all chords with a conscious rhythmic value to each note, that it has really changed the shape and flow of pieces, and brought a lot more clarity. I didn’t realize how vague I was playing even though I always finished on the beat. When you consciously choose to break some chords slower or faster than others you have so much more phrasing in your control. So, even if you always break chords, you have so much subtlety available to you. I think that it is just the voice of the harp, and the contrast is important. I think the rolled chord is more sensual, sexual and passionate because it is shaped, delayed, completed, and is more visually detailed.