I’m 100% behind your assessment of static content and your aspiration for Xibo. We have this recorded for 4.1 already, but I will link this feature request up to our internal issue for it (which we will make public once we have a direction).
My view on this is that the fly/fade in/out transitions we have currently are for use within playlists, and a new set of powerful animations be made available for elements/stencils.
Lots of scope here for what we might want to be able to do - twiddling text is definitely one, as are things like wiggling an image.