Rest assured that no testers have been harmed in the making of this game. As an ethical development team, we have a strict policy of only using brains of the naturally deceased, or lab grown brains. Full disclosure - while this hasen't happend yet, had come across a brain of considerable comedic value, the aforementioned policy will be disregarded.
We are looking into various possible hint systems, and also trying to make the difficu;ty curve more gradual by adding additional levels.
Regarding the last suggestion -have thought it's such a great idea, we immediately implemented it and it's working great, it will be included in the next update for sure.
Again, thanks for playing - your feedback really helps.