I'm going to go the other way. This will likely be a hard, thankless task that you'll never finish to your own satisfaction.

So do it. Fight it out, play with it when you have the time, write things down. You will wind up developing your own system along the way, and hopefully, get a better idea of how to develop your stuff. You might come up with something a lot of people enjoy, or you might simply reach some peace with the idea.