I thought they would have brought more past Josephs on - Philip Schofield, Donny Osmond,...etc, and maybe more past narrators and cast members. That being said, they probably didn't have the time (or stage space) for so many bodies, so went with three Josephs and three narrators.
Danielle Hope sounded great - I'd like to see her and Lee in something together.
Incidentally, I did wonder if something was up with Jason's voice - when he first came on, I wondered if he was miming because his mouth seemed slightly out of sync with the audio. It also felt as if his part was cut down. We had Joe doing his solo bit, Lee doing his, Joe and Lee singing together, then Jason finally coming on to sing his short solo bit before they all did the remainder of the song together.