Okay, so to make this game a true idle, you just need to make autofight advance to the next monster in queue. Better yet, let us set up a sequence of monsters to fight and then just click autofight and have the game fight them in sequence, that'll make getting all the Prestiges WAY faster
You should give the option to revisit lower difficulty levels. If you "rush" the dragon and get lucky with potions you can get stuck and be forced to restart, which is really annoying.