This utility is fantastic, but its utility is limited by the fact that it only supports frame-based animation. Although switching to time-based animation would likely require a fair amount of work, the approach seems relatively straightforward given that you could use a playdate.graphics.animation.loop to handle the frame tracking. Its properties seem well positioned to provide everything you'd need to support the current JSON config and API as it is today.

Technically this would be a breaking change and could impact some games when compiled against the new version, though you could minimize that significantly by setting a default delay on the loop object based on playdate.getFPS().