What's the Most Important Aspect of an RPG?

[Sword_of_Doom]

A good game must include great characters, npc, a world to explore, challenging combat system, wicked treasure to find and improve your character and a great storyline. The three games i have played the most, Morrowind, Diablo and Baldur's have elements of each of the above but not all. Morrowind has a great world to play in because its non-linear but the combat system sucks. If it had Diablo's combat system it would be much more fun. Baldur's is a great game with a huge world and great combat but sometimes the travelling and the quests are slow and pedantic. The more complicated the quest, the greater the reward.