I was part of an intial group of PMs and Desginers that was analyzing challenges our users faced while creating presentations. We discovered that many users struggled with adding content that didn‘t fit any of the slides in their company template. They might find something similiar to what they needed in other presentations or templates, but that usually came at the cost of brand consistency. That insight gave birth to the idea of "Layouts" – a collection of common slide types adjusted to match the style of the presetnation.
In the project that followed I reworked the slide picker in two steps. Initially I focussed on overhauling what we already had, repositioning the slide picker, solving known usability issues, and removing some overly complex interactions.
After confirming that useres would be happy with that change, we commited to the second step: Adding Layouts as a supplementary method for creating slides when the current template doesn‘t include what the user is looking for.