Although simple, the concept has a lot of potential for a  good brain teaser, the structure placements being impermanent was something that took me a bit to get used to, but once I noticed the possibilities it opened I was hooked.

In future iterations (if any are to come) I believe 2 things would make this more interesting.

1) since the idea is "reconnect with the magic lost deep in nature" a better representation of the impact level progression is  achieving to the kingdom in regards to magic would be nice, such as further maps changing visually, or new structures being available that use magic.

2) slightly more complex uses for the map layout, such as special towers that can work un-tethered from the central castle, they could be of limited use, or already pre-located in each map, working so the player can make greater use of the structure replacement more often and more strategically.

All in all, this is a great game concept as it is, and I would like to see it explored further.