Thank you so much for the in depth feedback! The specific numbers you gave me and the improvement ideas are tremendously helpful. Being able to buy a rooster is a good idea, it is something I've considered as kind of an intermediate between having chickens and buying upgrades (my partner was also super confused why she was picking up coins instead of eggs haha). The recommendation of making the foxes harder by having more of an ability to combat them is very interesting as well. I have been trying to find a way to make foxes (and in general the game) harder without cramping players' fingers spamming click/space, so the idea of an entity that attacks the foxes for you once they are too strong to click is def the way to go.
Yeah I mean by keeping my number of chickens low I also had an easier time focusing on the foxes when they did appear.
There could be a break in the action periodically, such as at night, if you want to give a rest to players... but there is a pause button anyway so I wouldn't think its a huge issue. (I used spacebar which is definitely superior for me)