That’s interesting you say that you feel the game is lacking an overall goal, I agree it seems a little open ended but I was thinking the goal was survival!
But adding specific things to destroy is a great idea, perhaps as you said, there can be tasks that compliment the overall survival aspect. I like the idea of destroying something or somethings. Perhaps eating all the bushes around 5 monuments or eating all the crops specifically from a farm.
Wind and fire are fantastic ideas! Perhaps even to the extent of you being able to be the cause of them by setting your swarm on fire to spread it to different fields.
I like the idea of chickens falling asleep too. They definitely would have a food coma after eating that many insects!
This feedback has been so helpful, is there anything else?