Nice! A small suggestion, the A/B buttons currently only react to onRepeat, so you need to hold them down a while to get a change and it’s hard to give the parameters a small nudge.
This reminds me, would it make sense for Arcade to provide a combined event that is triggered on both first press and repeat? I find myself often repeating the same logic for both. Extracting the common code into a function helps but is a bit clunky.
I filed https://github.com/microsoft/pxt-arcade/issues/3288 asking for a “onPressOrRepeat” event handler choice. (The name isn’t very elegant, but ideally it should be clear what it does without needing separate explanations.)
I responded over on the github issue, but there is a way to do this currently: in the controller extension
there’s a block to set the delay / interval for repeat, and setting delay to 0 should behave as you want.
And here’s an example: https://makecode.com/_Vvuasy3UXLwD