Oh, good question, and that sounds so fun!!! I think the prep work you're doing is really solid and a good idea. My first immediate thought on pacing to use one of the simpler alternate frames; the Beats frame is more or less how I game routinely now, whatever system I'm using -- it has seven "scenes" with specific notes to hit with one of those scenes repeatable several times if you have more time/want to demonstrate more of your chosen framing, meaning I end up with about nine or ten scenes, usually. The Point Buy frame also has a "repeated" scene you could reduce to running just once; it's more uncertain because how fast you move through it is predicated on your successes and failures, but has the advantage of being a bit less particular about what you "show" in each scene. 

Another option, more experimental, very simple, and I think inspired by Swords Without Master, would be to leverage your Motifs directly for a "snappy" and "tight" experience. Make just one d6 list (or one list each), add to it quickly (maybe even make a rule that every roll failure is a new motif). Once you fill the list up, stop adding and start playing each motif in turn as a callback, event, or re-contextualizing of the original events. When you've included or resolved six you're done. That of course relies a whole lot more on your scene framing tools and interpreting them quickly; I personally find I devote more time to setup/framing than to playing so I tend to build in a lot of tools to handle that aspect, probably even too many!