If I didn't include Clicker Heroes on a list of the best clicker games on Steam, there would be an absolute riot -- and for good reason. Clicker Heroes is definitely the most solid of the clicker games available on Steam.
While it is a bit slow starting off, once you get into it and start making some decent progress, it begins to show just how beefy it is with content. What can I say? It is highly addictive and satisfying to play. Once you start, you will find it hard to stop.