Well, if you're making a single player game, how much fun the player is having is the general thing to consider at the end of the day. Throwing in the banking system is fine by me, but adding in save points too may be annoying. If the player wants to reload the game, let them. If the player wants to cheat a little bit, I'd say let them. Chances are, they'll enjoy your game more for it, at the end of the day.