Of course the early levels are going to be easier...that is how they introduce you to the details of the game. However, if you work through the early levels, you will see that this game quickly becomes a true time management game. Just clicking every task like mad will not get you three stars on every level. Is it the most challenging time management game ever? No. But it is still an enjoyable way to pass the time.
I almost passed this over due to the cartoonish appearance of the game. In my experience the more cartoonish the appearance, the more ridiculous and stupid the game. This is not the case with this game. I haven't played the entire game, but so far, I am impressed. You do need to take the time to think which route to take to make sure you have the right resources to accomplish the tasks. It is far more than "just click on every available resource" or "just upgrade every building" to get through the game. You need to take the time to decide if making that next click is going to benefit you as you move forward or is it going to put you in a situation that you can't recover from. I have had to restart levels because I chose the wrong route and there was no way to get the resources I needed for the next steps.
In other words, despite the cartoony appearance, this game makes you think.
I enjoy this series and developer. This one is similar to its predecessors, but just enough different as well. I find myself needing to rethink my strategy and approach to the various levels, which is a refreshing change. To get three stars you may not need to click on all the things or improve all the buildings. If you do, you will be challenged to reach three stars. This game actually makes me think. I had no trouble with the game running, unlike other reviewers.