Improved AI Required by builtin bots anyway. More precisely, simple sensor-effector mappings in compact lookup tables could add a lot to the game. See e.g. Valentine Braitenbergs Cybernetiv Vehicles . A server side bot would add some incentive to improving the builtin AI, a client side bot would encourage an engine design which allows using the builtin AI as a client bot toolkit. See some article for details, references and pointers.
Standard rating has to be tied to a builtin DM mode.
Display settings have become utilizied as means to gain advantages in deathmatch. The ability to turn off certain modifications of the rendered image, like full screen blends, also improve visibility of opponents. Autoupdater Like Symantec's. The big concern is that it NOT get in the way of the advanced user. Autodownload See Quakeworld.