Secondly if you want to be successful you must think out a new or different approach to the game theme, another Oblivion, Two Worlds, The Witcher or similar will drown in the shadows of these games if it can't show up something new or thrilling.

Indeed this is true of any type of game. Coming up with the setting, the world, the intire presentation that has to be 'yours' and not a poor carbon copy. In RPG's the setting and the main story and related quests have to interesting. You have to get the player to 'roleplay' and stay engaged. Quite frankly Oblivion fails in that in my opinion and succeeding in that area is easier said than done.

Talented writing really comes in here. Unlike many other types of games like puzzle games here your almost relying on talents in other fields. Now if your the next stephen King or have the next AD&D system in your head your be one step ahead.

Take a look at games you really liked and try to analyze what exactly they did that you enjoyed. For me Fallout got me in several areas. It was top down- something I really don't like in RPGs yet it succeeded. First the combat had a strategic element. Like Betrayal at Krondor or the old Gold box series it wasn't a mindless clickfest ala Oblivion. Secondly the setting worked. Dark and harsh. It satisfied the sci-fi fan in me. The disney King Aurther pretty world of oblivion doesn't. This by the way is in drastic conflict with the series. Daggerfall had a dark world much as The Wicther had. Morrowind had a very Alien feel. Here the eye candy actually works against the game for those famaliar with the series.

Thirdly the writing and engaging quests of Fallout. They 'fit' with the world. So did the options. Pimping your wife out for Bottle caps was to be expected. The quests were interesting and had interesting twists. Sorry but though I find the quests in Oblivion a bit better than Morrowind as a whole they are mostly boring fed ex deliver type quests. I really didn't care if I ever finished the game. You have to do better. Fallout was a game I had to finish to see how things turned out.

In a RPG you better have this stuff before anything 'game' is thought up in my opinion. If not then your need a writing partner that does. This is the one area you really HAVE to be good at. If you are players will forgive other elements like poor graphics and even poor game mechanics if the overally world and story engages them.