I learn (making games for the Playdate)

I've been considering getting a Playdate as a means of having a constrained environment to develop a small game in. I didn't realise there has been such a long wait to get one, so perhaps I should place my order soon?

I like your suggestion of time-capping the development time. It's definitely easy for small, personal gamedev projects to grow in scope. In the past, when I've "finished" making a game (it always feels like there's more I could do), it's typically been because there has been an external deadline (e.g. a competition; or in one unusual case many years ago, advance warning on an upcoming change to the Apple App Store developer ToS, which threatened to only permit apps made directly in Xcode and potentially meant my WIP Unity app would not be approved).