i think it was mostly the change of pace. You have: multiple choice -> one button for choice, True or False -> one button for each, I think it would have made more sense just making a direct imput for the answer (maybe buttons from 0 to 9 to type). After all, either you knew the answer or you didn't. The mechanic didn't really add to the difficulty, it just made more tedious to aswer. Of course that is just my opinion and don't take it the wrong way, I really enjoyed the game!