What about putting a lot of quick time events (QTE) in your game? I hate them! I once made a demo for a game in which you had to shoot down 6 enemy UFOs while flying around in your spacecraft. Only later I discovered that the sixth was so badly placed in the scene that even I couldn't take it down. I didn't correct the demo, and a lot tried it and left frustrated. I will never do it again: scout's promise!