I keep tinkering with game design / programming stuff but get side tracked all the time by too many ideas. I'm going to make a few posts of ideas that I'm not going to pursue but which are taking up room in my only modestly sized brain.
None of these are my ideas exactly - I picked them up from various places and I'm just applying the concept to an MMORPG.
The game world is the size of a middle-sized game continent/island like Northrend in WoW or Faydwer in EQ and it slopes upwards to the centre. It's all one big city.
The city is divided into six or seven levels like the tiers of a wedding cake and the tiers are separated by walls. Each tier is further sub-divided into dozens of quarters and sections. There's slum bits in each tier and some nice bits in each tier (even the lowest tier has sections where the rich keep their pleasure boats for example) but the proportions follow the usual pattern - the top layer is mostly rich and the bottom layer is mostly poor.
I was thinking of this more as a skill-based rather than class-based and possibly a more PvP type game. The aim is to take your guild from the slums / fishing quarters up to the top tier and would mostly work on building up the guild reputation and thereby gradually getting offers of work from higher up the tiers. There'd be abandoned buildings to use as a base in tier 1 then if you moved up you'd have to leave that behind and create a new base on tier2 etc . The aim would be to discourage guilds recruiting newbies from the lower tier but to form up at the bottom then move up as a group so maybe a max number in the guild.
There'd be no law in this city except the law made by individual factions so one section might have a fishing collective who have their own militia another section might be run by the baker's guild etc. The player guilds would often be hired as a guild to either trash or defend one of the city factions. There'd be solo and small group missions as well - the reward for completing these would include adding points to the guild reputation.
Players in the starting tier would be PvP immune until they joined a guild. Players could choose the solo path all the way but it would be harder. There would be solo missions to increase their solo reputation but these missions would involve conflict between two of the city factions and eventually they'd run a mission where another solo or a guild was attached to the faction they were attacking. This would flag them for PvP and it would be a one way thing.
As well as solo missions, if a guild that was below the max number had a mission and they needed extra bodies they could attach solo players a bit like open warbands in WAR. If they had a guild mission to go trash a gang that ran a certain section of the city and they didn't have the full 24 then they could make it open and solos could join temporarily. This would make those solos immune from attack by that guild until the end of the mission plus 5 minutes or something like that.
Solos would rise through the tiers of the city in the same way as guilds - by increasing their reputation till they got a mission from a faction in the next tier up.
There'd also be non-combat soloing via tradeskills and suchlike. Tradeskillers who never joined a guild and who never joined in a guild mission would stay PvP immune.
The game would mostly revolve around player clans though.
Although the city was all humans there'd be plenty of cults and demonologists and witch covens in the basements as well and the whole island would be built on top of a gigantic cavern with demons and **** for variety.
A lot of the missions could revolve around food because the basic diet was fish and there were too many people for any large farmland so the richest factions had walled off enclosures where they could grow wheat and a loaf of bread would be worth a lot of money. Also factions would have chicken coops and pigs etc and missions would often revolve around stealing another factions chickens because any food that wasn't fish was extremely valuable.
Eventually the clan would reach the top tier and a final fancy base and work to max their reputation. Once the reputation was maxed they could try and take over as Overlord.
This would basically involve some kind of instanced battle where your clan attacked a palace battlefield and had to kill the Overlord within a certain time.
The first clan to do this obviously would be fighting NPCs (or maybe the devs) but after that the clan would be the new bosses. The "endgame" would be trying to stay there as long as possible while other clans came up and tried to replace you. The battles would be instanced and timed for the prevalent timezones so everyone could be on and they'd be maybe an hour or half an hour. After the game had been running a while the Overlord clan might have 2-3 battles a night queued up as other clans tried to take over.
One of the defending players would be designated as the Overlord - usually the guild leader or one of the officers if the leader wasn't logged on and the attackers would win if they killed him inside the time.
If the Overlord guild lost then either they lose all their reputation and gear and go back to the slums again as newbies or perma-die or something like that that would provide churn and "new" blood at the bottom of the pile.
The challenge would be to see who could stay as Overlord the longest.