For long jams like this one i usually pick a subject and try to do as much of it as possible to learn by doing, so for one jam it was ui, for another one vfx etc
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So what's your subject for this jam?
Is it focused on a genre, a mechanic or is it something a bit broader?
At the moment my UI and VFX are normally quite simple. The limits in a jam, my own inexperience and my own desire to make my own assets limit how much time I can spend on some aspects of the development cycle, but your approach definitely sounds solid.
For this one i was going for vfx but this time i've strayed away from my own mini theme cause i like the concept and i don't want to make this game worse than it could be if i was doing my usual approch. So it's basically do i want to get a game out of the jam or knowledge, this time i decided on the game