These alerts are not ideal. You can’t block because then you can’t interact with the alerts which run in the main thread. So they are what they are. (sigh.) I’m figuring you can use one per playground page if you really have to.
Of course, what playgrounds really need are embedded controls, reset buttons (revert to distribution set point, allowing exploratory tweaks to undo), and audio and video narration. Among many other things on my list.
Today, I put together a SpriteKit tutorial proof of concept. My primary tester had to spend nearly an hour just getting the thing running (you need the right iPhone Simulator installed with the right OS / I suspect it’s one of the 6’s) just to spend about 10 minutes looking at my “see what Playgrounds could do in terms of SpriteKit training” stuff. He liked the SpriteKit bits but the playground parts are putting me way way off this concept.
Anyway, here’s some code. Do with it as you will.