I've made a few changes to the structure of mysteries today that aren't very obvious. I'll let you figure out most of them. A few important things though.
1) The harder level mysteries are probably a little tougher than before. If you find yourself having troubles, you might want to move down a level for awhile.
2) The number of suspects is no longer static on ANY difficulty level.
3) If townspeople / shopkeepers know anything about the case, and the person they know about isn't already visible to you, they will now become visible. You will not automatically know their motive though. This should make the non-physical evidence contacts more important than they used to be.