I know about the jam, because I also made a game for it.
I would not get rid of the fog, but I would still make it a bit less foggy.
The enemies is not bad, but because they all look a bit alike and most of them seems to attack in nearly the same way, they feels a bit too similar. I know it can be difficult to make a lot of different enemies in a jam game, but then perhaps only make two very different enemies types.