I developed this idea when I was away...
I think it would be interesting if there was an upgrade to the way we gain stats for logging in everyday. The concept is that perhaps there could be a place for apple trees or some sort of fruit that grows in a location. These fruit can only be collected by players once a day, and are used to increase different stats in small amounts. For example, a red apple would increase a players attack skill, while a green apple would increase the defense skill and the yellow would increase your regeneration skill. These items would be similar to a resource, but there would be a clickie on screen for them. The method of determining which particular piece of fruit you obtain each day could go one of two ways. Either you chose the one you want, or it will be given randomly. In addition, there could be some sort of pie or fruit salad recipe that requires a certain amount of all fruit, and some other items. This item would have a collected stat bonus of the fruit added, plus an added stat increase.