Very nice start, especially for your third ever game jam! (I'm pretty sure my past ones suck)
For improving it, apart from more content, perhaps you could limit the amount of objects you can place, which will avoid just brute forcing the game and if you add more levels, it could turn out to have some very interesting levels.
If you do have time, I would very much appreciate it if you could rate my game here: https://itch.io/jam/wowie-jam-4/rate/1663155