This is an interesting topic and I very much enjoyed hearing your thoughts on it.
I’ve only used clocks when I’ve run Scum & Villainy but there I found them quite effortless, assuming you put some thought into what you used them for (i.e., nothing that is quickly resolved with a single roll).
I used a similar technique to replace skill challenges when I was running D&D 4E, though I’m honestly not sure if I started doing that before or after I read Apocalypse World. What I ended up with there was a fairly involved mini-game that was fun and interesting but sadly the class imbalances in the 4E classes made it a bit wonky. (The Bard with Jack of All Trades always had a lot more options than the Str Cleric, and fixing that would require fixing the whole skill system which I wasn’t really up for at the time.)