I would not separate your group and keep checking back for earlier reservation times. Have you signed up for the free touring plans reservations finder?
We’ve done dinner there twice (2016 & 2018) and enjoyed it both times. We opted for dinner because we did not want to rush through the experience. This meal takes a bit longer than a standard one credit table service meal (we usually plan 2 hours for CRT) so a PPO breakfast will likely cut into rope drop and morning park time if that is important to you.
In Feb 2016 we had a 6pm reservation and caught the 8pm fireworks during dessert. They dimmed the lights and piped in the soundtrack for the Wishes fireworks show. Obviously the view is not great but, since we’d already seen the show the night before, it was a fun ending to our meal.
I’m also in the camp of go for all the princess meals/experiences before your daughter outgrows that phase. Our family loves character meals and, although we know the food is not usually the best, we still plan one for almost everyday of our trip because we love the unique Disney experience!