I know it's still new but I think it would be great to add a feature to open the house into one room (or two), when you click on it. Also to be able to place your kao-chan(s) in the garden.
Other then that I think kao garden is great! I love being able to build my garden as I study.
Most to all of that is going to be implemented exactly as you said, or planned in a slightly different way. We have tons of plans, but we want to introduce it a bit at a time.