Congrats on your first game jam! This is only my second jam, but I definitely agree on the hard deadline thing! It really helps to get yourself to push forward and finish things instead of endlessly tinkering.
At first, I planned this game to be a one-off, but I wasn't able to implement any actually interesting level design. I still like the concept, so I might try to develop it into a bigger game, but in the end, it will probably still be something small. Definitely not something I plan to devote more than a few months to, but who knows!