In my opinion giving that much freedom (all those settings) to user is not good and ruins the gameplay. I'd prefer such game to start simple and increase diffic

In my opinion giving that much freedom (all those settings) to user is not good and ruins the gameplay. I'd prefer such game to start simple and increase difficulty by itself. I find this one almost perfect: http://games.usvsth3m.com/maths/ http://games.usvsth3m.com/maths/ although it lacks more levels.