Yes, I do like the conceit that the the camera viewpoint is also looking at the angels. I think it makes them much more effective. That said the angels really do not move that fast, no matter what the Doctor says and I'm not sure the episode needs to imply that they do.

I think they were worth bringing back, but agree they botched it. But I'm only half convinced that a monster has to be scarier, more dangerous, more ambitious, more whatever on each appearance and I think Doctor Who frequently falls into that trap with all its monsters. You can tell a different story about a monster without having to play some kind of escalation game.