I haven't found much difference in the three levels. Hard really isn't any harder for me than easy. I've had no problems on any of them. Luckily, I haven't had any events wipe out all my food or get my berries until I had farming or my crops until I had fishing. As long as I wait until right before I have farming to have my first child, I have no problem. Of course, I am a micromanager who can barely stand to leave my villagers alone (especially early in the game) and so I check in on them often and pause if I'm going to be gone a while.