EDIT: Also, I don't care for modern day settings. I live in modern day. I want to escape from modern day. So my ideal settings are Futuristic Sci-Fi or Mythological Fantasy.

Now that I can agree with completely! lol So bored with all these zombies and urban fantasy... I like alien historicals and low fantasy romance best, but I like pretty much any sci-fi and fantasy that isn't too grim and gritty or conversely filled with elves and dwarves or petty gods killing people off for their entertainment.

I partly agree with the OP and I'm actually planning to create an Fantasy MMO myself.

About social part, I know what you mean. I decided I want to make it turn-based and PvP only. That way, people HAVE to work in teams. Also, turn-based games are not as intense, so you get time to chat with your friend / foe. This also fixes what you said about everyone facing the same mobs and everyone being the same, because there are no mobs and quests, only PvP.

Another concept I am trying to enforce is freedom - there will be a large variety of builds available, not limited by classes. I want to give people the option to name their own class, so that's gonna keep them creative - they can look up a really powerful warrior build for example and then go like "nah I don't want this skill so I won't invest in it as much, but I want a heal" and then get high HP and make their class "Tank" or "HP Warrior" for example.

I am really hoping to make it 100% F2P too, so there will be no subscription or cash items or anything, but we'll see how it goes.

I don't want to limit the number of players, but I doubt it will be that much of an issue.

Tell me what you guys think.

I don't necessarily care for a story in the sense of Guild Wars where they make it sound like you are the chosen one. I play an MMO knowing full well that I am dirt and must work my way up. I prefer a game that allows me to create my own fun giving me a large platform to do that with. An example would be Ultima Online in its earlier days. You were just as good as anyone else with relatively short work but you found your own way to play the game. That sentiment has been lost in recent MMOs focusing on scripted quests and giving very little in the way of creative freedom.

(Remember, I'm broke as a joke, so I'm not looking to actually produce any of this. This is a purely hypothetical discussion.)

The most basic idea behind my original post was to get away from the "Massive" portion of adventure gaming, but still be able to play with a reasonable amount of friends in a persistent world. This eliminates auction houses, gold farmers, and spawn camping almost entirely. Why even bother adventuring if you can grind up enough gold to buy the latest and greatest in equipment that other people went out to get? Why bother playing at all? There's no story or fun to be had there. (But... it's FUN being powerful! Well... why don't you EARN that power yourself instead of just PAYING someone else to play the game for you?)

The business model I had in mind would be to rent the new worlds to the players by server. There wouldn't be any buffs or shortcuts for sale. A player or group of players would prepay for a fresh, unspoiled world to be spawned where then they could log in and stomp all over it as they pleased. Griefing would be mostly eliminated as the players would (ideally) already know each other and have social repercussions for their actions in the game. Strangers and bots are up to the managing players to allow or disallow. Items would be locked to that singular world and not available for cross-server trade or sale. I think this would foster a culture of cooperation rather than competitiveness between players.

What you’re describing sounds a lot like a Multi User Dungeon, rather than an MMO. (essentially a video game version of D&D) In a MUD-like game, actions have a permanent effect on the world and the focus is on completing the dungeon/quests as a group, whereas MMOs are meant to be persistent and open ended worlds where everyone can run through the content in their own time. This leads to the mindset of everyone in an MMO being out for themselves, since the incentive structure is built around personal character advancement, rather than working together to beat the game. In an MMO, people typically group up because they want to get X item from Y boss, whereas in a cooperative RPG, the focus is more on actually accomplishing the mission than grinding for gear.

You could think of any co-op RPG as being a kind of multi-user dungeon on a small scale, but they're usually much more linear than MMOs and it’s pretty rare to see them on a large scale, (requiring more than 4 or so players) especially in recent years. The main problem as I see it, is that for the game to work, all the players have to pretty much enter and play at the same time, and that means already being friends; you probably wouldn’t want to join a public world and find that most of the monsters have already been killed and there’s nothing for you to do. From a business perspective, it’s difficult to sell a game (especially if the plan is renting out servers) when you need to have a large group of people in order to play, since potential customers essentially have to organize a group beforehand to really get the most out of the game. These kinds of games really have to be built on top of a singleplayer RPG or else with a free to play model to remove the risk of buying on your own and then not being able to find enough others to actually play the game.

...for the game to work, all the players have to pretty much enter and play at the same time, and that means already being friends...

That's pretty much what I'd like. I don't see that as a problem, but as a strong selling point!

...you probably wouldn’t want to join a public world...

EVER! Public worlds are chiefly what I'm complaining about. I'm largely antisocial and plan on being an old crotchety man in a few decades... I don't care much to play with strangers online or in real life.

If there is a problem with this business model, then I agree that it would be about the part where players would have to organize themselves before purchasing a world. So there would have to be some set of scalable selectors during creation to adjust the world to fit the population of players.

...for the game to work, all the players have to pretty much enter and play at the same time, and that means already being friends...

That's pretty much what I'd like. I don't see that as a problem, but as a strong selling point!

...you probably wouldn’t want to join a public world...

EVER! Public worlds are chiefly what I'm complaining about. I'm largely antisocial and plan on being an old crotchety man in a few decades... I don't care much to play with strangers online or in real life.

If there is a problem with this business model, then I agree that it would be about the part where players would have to organize themselves before purchasing a world. So there would have to be some set of scalable selectors during creation to adjust the world to fit the population of players.

I think a lot of people don't like being flocked by a bunch of griefing noobs. I'm beginning to think the answer lies in persistent elements and localized multiplayer with a system of checks and balances to keep it all tied down (similar to how bitcoin can't be hacked at the moment). For example, a global market and trade mechanisms with localized quests and events that do not effect the larger persisting game. However, it really depends on your objective with the game and some people like to have people running around ruining stuff for no other reason than its a good show.

Maybe what you're looking for, then, is a really well-designed multiplayer campaign for an existing game. I think Neverwinter Nights might have the tools you need to do this.

An alternative to cutting the number of players could be to design the game so different players can have different goals and quests / missions.

That would be to make the game more sandbox,so instead of having a game focused on a single thing to do and every player having to do the same thing,you make individual story lines and maybe factions,or jobs or other stuff,that are designed to be fun on their own and not having a supporting role.

Take a look at Grand Theft Auto for example.

It has a series of racing missions,a series of linear shooting missions,another 'mission' that will have the players explore the world to find and kill / collect / whatever all "X"...

The point is that in Grand Theft Auto,the player chooses what suits him best to his own tastes,and he does that. So there are some GTA players who only do the shooting parts. Others enjoy racing and spend their time racing....

Now imagine how that could work in an MMO world.

There would be some players spending all their time on racing. While these people would do races,others would fight each other in a let's say "Team Deathmatch" fight. Those racing wouldn't care for the guys being in the mission of TDM. They could just run over a squad of a TDM team and kill them. This would make it kind of more believable from a point of view,but in the same time it would make players feel that they have an identity - Those racing are different than those shooting. Those shooting have entirely different thoughts and goals than those racing.

The thing is,everything has to happen in the same 'world' or 'instance' for this to work. If such events are happening in different instances,the shooting guys are never going to see cars speeding in front of them. And of course that would mean that there would be less 'safe' areas in the world,as PvP could come up when the players decide,in the same world everyone is playing. It would also require from players to be more safe because of that.hmm..