I really don’t know why this isn’t a bigger issue for the community. A great map editor (or map creator) can solve any problem you can think of for the game. Look at Warcraft 3 (PC RTS), which had one of the largest and most diverse modding communities in all of PC gaming-land. The traditional gameplay for Warcraft 3 was good, but it wasn’t great and was considered dumbed down from its more hardcore brother, Starcraft. What Warcraft 3 had that separated itself from other games was its easy to use map maker/editor. With this tool alone, amazing games such as: DOTA, Battleships, Footmen Frenzy, Wintermaul Wars, Hero Siege, Tree Tag, Vampirism, DBZ Tribute, Battle of Helms Deep, Pyramid Puzzle, LoaP, Team Line Tower Wars, SWAT, and thousands more were created.
This is how you create a game that lasts half a decade. You give players so many choices in how to play that it implodes their mind from the sheer godliness of the game. Halo being a console game is no excuse. If the map editor/maker has to be on PC while the actual game is played on console, then so be it.
You will never go wrong with including an amazing map editor/maker with your game.