I enjoyed the Imagine Earth demo. So much that I have backed them on IndieGoGo. I think this game is a good fit for those that like city building type games, but don't want them to be overly complicated with having to micromanage lots of different structure types. It's has only a few building types (that will have different versions to use as upgrades in the full game) but its main mechanic is in placement and their effects.
It has a nice easy to use menu system. Buildings needed to satisfy your cities basic needs are just a few basic structures for Power, Food, and Goods. The strategy of the game is not having lots of types of buildings, but strategically placing the building to give you maximum production while balancing their effects on citizen’s happiness and global pollution all while maintaining a positive income. This game is almost like playing chess with regards to having to plan your moves ahead of time in anticipation of when you begin expanding your city.
I can't wait for the full alpha version to release so that I can experiment with the different upgraded buildings. They will make it a better challenge, as they have different tradeoffs like they can give a lower pollution level but at a lower amount of the resource they produce. They will make it more challenging to keep your resource levels where you need them when you’re trying to minimize your global environmental effect.
Note: Some reviews have mentioned that it got annoying having to pick up the tax money from the city all the time, this is no longer the case since the March 2014 update. Taxes are automated, it’s just mining and bonus money bags you must manually pick up. So good job to the devs for understanding the players didn’t like having to do that and fixing it.