hardcoe mode - on/off (eating, sleeping and drinking to survive, why it called hardcoe mode i don't know, i'd implement this as normal game mechanic and have the option without it called "easy mode" :hehe:
Dungeons re-populate - on/off (npc monsters/bandits return to dungeons and caves some time after you kill them there)
Finishing moves - on/off
Thats all i can think of, what do you think of this? any more features in the game you'd like to have a choice over?