Games that require outside knowledge are always pretty hit and miss depending on who's playing, but your hint system built into the mood of the game is a great idea. Reminds me of early browser games.
Some of the puzzles take an irritating amount of time to decode simply because of the choice of solution, e.g. using long words when short words would do, meaning there's a gap of time where you've solved the puzzle but have to do the grunt work to get the payoff.