Complex idea, simple system of play, very easy to caught up in.
Other than that i could see this idea evolving into something really cool over time if given the love and attention it needs. As for the game play, its quite simple and fun. Understandably slow for the first few minutes as you must first create to be able to reap the benefits... much like the initial ground laying in Sim-City games. There is a glaring error in the camera/defense controls that can cause your camera to spin in battle if you move and block at the same time. I have quickly learned to resist that and i doubt that it will hinder play too much as the game area were combat takes place is not too complicated or large.
The characters in the game are quite interesting, from your typical market girl to a stoic builder. Personally i have grown tired of the hand drawn-like, still image characters that the PSP seems to be plagued with but for a game like this it keeps the flow and is well fitted. Overall this game is for those who have a vast imagination. If you ever played an RPG and thought to yourself that you could build a better dungeon then here is your chance. Don't worry if your dungeon seems lifeless at first. You'll soon get into the flow and realize that the game has some subtleties that need to be discovered as you play.