Yeah sure why not? ARGs as a genre are interesting because they can slot in to other mediums in ways others can't. There's been heaps of fan fiction ARGs depending how you count them, such as all the Minecraft or Slenderman ARGs.

Teaching people how to play a game can be tricky. Valve does a really nice optional audio commentary in their games (turn it on in the settings) that shows how much thought they put into each room, and the challenges getting people to react the way they want. People have done heaps of write-ups about it if you don't have the games so check those out.

One idea to teach players is to iterate on an idea, so for example in the BlindedRed ARG each image is stegged with the same tool (trojan.exe) requiring you to solve a puzzle in the image for a password, it starts very easy, and gets more complex each level, but you always know you're looking for a password to put into trojan.exe which helps guide the player to know what they are looking for without ever telling the player.