i think its helpful to compress the base concept. I did a top down puzzler recently for a jam and while ideally i would have liked to have fifty levels, i just didnt have time, so made ten to demonstrate the core concept. one could hypothetically contain all of the elements of a metroidvania to just a few rooms, or even one area. i bet even a single screen metroidvania could be possible. im kind of happy its a month because it gives some time to develop more content, but it will still be important to consider scope.

All of the above. Also I'd like to emphasise a smaller game that's made well is much better than a longer game that people get bored of. Leave players wanting more