I think the way in which you and your team decided to split off and come up with unique individual ideas for the overall pitch you went with is really interesting.
It's tempting to just go with the idea of the pitch someone suggested, without considering what others would add, but this solution is a pretty good fix for that problem. Having everyone pitch smaller ideas related to the big pitch idea you went with is a great way to expand on it. I wish you and your team luck.