That makes a lot of sense - having a deterministic recording makes a big difference to learning how the code actually works.

I also sometimes think that, even when I want a debugger interface to look at the details, I'd also like to see a "big picture" view showing how key values evolve over time.

(something like replay.io does for visualising logging statements is probably in about the right place for both of us, though I'm not a web dev)