This was a brave idea for a game jam! I think you did well with the time constraint :)
The main problem i had (aside from the idling part at the start which i understand was a design decision), was that I didn't really know what a lot of the shop/mayor purchases did. I kind of had a rough idea but some sort of tooltip or info button would have gone a long way to at least make me think my decisions weren't as random :)
I also didn't find the shop for quite a while :) maybe that was just me but it wasn't obvious to me at first.
I finished in 308 days by eventually going all in on nuclear and realising that migration massively sped up population growth :)