Big long rambling rant about MMO's ... GO!
MMO's need to stop looking to single player games to determine what mechanic, or character advancement model to steal next.
A single player game will always provide the superior gaming experience for an individual. From detailed story lines, to perfectly placed and timed skill advancement, to incremental expansion of the game space, every element can be controlled in order to ensure the player is receiving the maximum impact from each design decision. A single player game is there to offer the best marriage of story, art and gameplay possible.
So where do single player games fall short? Single player games struggle hard to offer a compelling reason to play them more than once. About the best they can come up with is to tell the same story from different points of view, have branching story lines, or increase the stats on all of the challenges and rewards and let you do a new game +++++.
Single player games also offer little to no chance at social interaction and are hard pressed to offer a truly random or unscripted experience.
So... when an mmo builds itself around single player gameplay mechanics, and offers a narrative that targets one player at a time, and tries to recreate that single player story telling experience on a mass scale... it is going to suffer an identity crisis.
On the one hand there is going to be a volume of content, hand crafted by the developers, that will move the player through the world on some leveling adventure and character advancement saga, but once this story ends, the game either turns into something completely different, or stagnates until the developers release the sequel, err expansion pack to their leveling adventure game.
In-between these adventure games, there is usually some attempt at social gaming through pvp or raid encounters. However both of these elements suffer greatly because of the single player focused leveling mechanic. Pvp is not allowed to go outside to play, lest it disrupt the leveling narrative, and becomes some isolated affair. Raids tend to take on the aspect of giant sized single player boss fights, just with a lot of people attempting them concurrently.
Scripted content is time consuming to produce, and requires some additional mechanic to encourage players to use it more than once.
Therefore MMO's should always play to their strengths, those strengths being social interaction, opportunity for unscripted content and player driven encounters (pvp and other methods of players creating objectives for other players), the ability to create a sense of permanence from one's actions and allow those actions to be perceived by other players.
And yet, these strengths and unique facets of the MMO space get the least amount of focus in just about every title released in order for some half assed leveling adventure game to steal the spot light for 60-100 levels of the player's time.
A few things could be done to remedy this.
First, character advancement needs to take a back seat. That's right, leveling should not be the game until you hit the hard cap and then start playing a different game with the same name. Leveling should just occur as a result of playing the game, and should have a soft cap that gets exponentially harder to reach. This prevents the hurry up and wait mechanic of the unlocking level scheme that most mmo's use with their expansions.
Second, other players need to be integral to the game play experience from second one of day one. Nothing worth doing should be a totally solo experience. That is not to say that you need to have other people actively working side by side all the time. But every goal and achievement pursued by an individual should be created, challenged or in some way influenced by other players. So when you are down in the depths of an abandoned mine that has become infested with goblins, the reason you are in the mine should be one of the following:
A.) Because another player is looking for a rare ore that might only be found there.
B.) Because another player has decided to use the mine as a base to set up his goblin army.
C.) Because a player built settlement nearby is worried the goblins may start attacking soon.
D.) All of the above.
Third, developers need to stop worrying about people messing with each other and putting up a million artificial barriers to ensure everyone has the exact same experience. They should be giving the players MORE tools to interact with each other. Player interaction should find it's way into almost every single aspect of the game. This is an mmo, why anyone would go through all of the effort of creating a game space that can be accessed simultaneously by thousands of players, and yet put glass walls between all of them so they can't do much more than look at and talk to one another is beyond me. It seems like such a waste of effort.
The smart developer will figure out ways to keep the experiences mostly positive. Or to incrementally introduce a player to complex interaction systems so they are not overwhelmed. But ultimately the training wheels should come off and people should come face to face with one another and not be certain what the other side might do.
Fourth, the power disparity between two individuals should be minor in the grand scheme of things. A single player's character should only be able to become so powerful. The real power should come from numbers, and then again through coordination. 10 brand new players should be able to pose a threat to any individual if they play their cards right and have a good plan of attack. The chances of true noobs being able to achieve this is minor as a veteran player will being taking precautions to prevent such silliness. However, anyone who lets their guard down should be at risk.
This right here will encourage player cooperation more than anything else. You need to band together to win at just about anything. If someone complains that they can't do anything by themselves, remind them what type of game they are playing.
That's enough for now... but other elements to tackle would be the role of NPC's in this environment, narrative delivery and world events, possible player roles.