Thats a really fun concept. I love the idea of digging around mails and stuff to find more information. I honestly think if you took that Idea and make it into a thriller story, so e.g. the player got accused by murder and has lost his memory and has to find out what happend, that would make a really cool full game!
I think gameplay wise its fine just the UI need some work, the font and panels could look a bit cleaner, maby with a retro computer look or something.
Overall really nice game :)!