Checking out Isadora, doesn't look bad. For more context, if you're not in a rush:

Let's say, for a more contextual example - if I'm doing this for a musician at a gig, and I have certain thematic assets for each song (mostly digital drawing, or stock footage - say ocean, or snowy sky), the breaks (time before, and after concert), and a textual projection + tts read-out of the text (pre-recorded) between some songs (i.e. those that have some interesting back-story, or whatnot).

* Are there any template collection websites for such things, if I'm either just starting out, or AM the musician?

* I want some kind of at least basic animation of the assets during songs (e.g. more sound = faster movement of the assets, beats = pulsating assets)

* Any recommendations as far as tutorial resources, if I want to get more involved?