This isn't the best way to evaluate software. If you were to look at what has been accomplished by inexperienced, independent, one person game developers (the typical "game maker" community member) with powerful libraries like SDL, SFML, and Allegro - you would be completely underwhelmed. Unless you have very specific needs which you should ask about here, C2 is powerful enough. Graphics are just decoration, they have no bearing on the abilities of the underlying engine.
Also, Game Maker has 10 years on C2 so of course you'll find many more complex games there. Does that mean it's better?
On a side note: I really wish Game Maker didn't own the name Game Maker. It makes it really hard to talk about game maker software in general.