I have a on-going project/client that frequently comes back to needing transitions that would fall under the moniker "2.5D postcards in space" This is not a put-down, by that I mean 2d panels in space flipping if a faux 3D way to get me from scene A to B.
Keynote does (I think) some neat transitions in this style and I've posted questions about this in the past. As I look to do (research) more of this in FCP, I'm groping for the right terminology because as I Google "Final Cut 3D transitions", I usually get results about extruded 3D or stereoscopic 3D and that's clearly not what I want.
Finally, I don't think Motion is a good return on investment (of my time) for this. In a perfect world the solution would be assume 3rd party FCP transition plugins. Part of the reason I've resisted Motion is because I'm pretty invested in After Effects and for all its capacity it's not exactly a transition machine.