Ok so here's my very sketchy wireframe MMO idea written in a few mins while avoiding real work. :P
I agree Neko the simple Kill Foozle, Get X doodles has got to be dressed up a bit as its getting rather stale. I understand that its easy to program but its not very engaging. 
Maybe something like this?
Ixo the Fighter is created and enters the world. 
He joins the fighters guild. They hand him a sword and shield and a bit of armor and after a few intro quests to become familiar with the game system they say apprenticship is ready to begin and start offering jobs for him. 
To start: 
Light Caravan guard duty - An overprotective merchant wants to make sure his goods make it to the nearest town. 
Contracted guard duty - A tavern owner needs someone in the shop all night for protection against a threat from nearest thieves guild. 
Hired out - An intown temple needs help clearing out a sub-basement level which has collapsed. 
Now in and of themselves nothing too fancy with these quests. However the potential for sub quests within each is present. 
Ixo choses light caravan duty and starts off with merchant train, following a dotted line ala Indiana Jones until near a river, the caravan is attacked by brigands. Ixo and the other guards are on the offensive and either kill the thieves or fail to stop them from running off with the goods. 
If they succeed they continue on with no more troubles. If they failed the quests opens up and either the merchants does or does not want his merchandise back. If he does, Ixo has the opportunity to pursue them to a nearby ruined church to take on the bandits on their home grounds and get the goods back. 
Either the bandits are all killed or the goods are sneaked out but either way completes the sub mission. 
The merchant is happy to have his stuff back but perhaps the game notes he find an odd statue amongst the goods returned which wasn't a part of his goods. The merchants grateful lets Ixo keep it and it spawns another quest to find out what it is. 
It doesn't happen all the time like this, the caravan could instead be attacked by killer bees, could run into a horrid fog bank and have to plot their way out while worrying about strange creatures in the mists, a wounded man falls before the caravan and indicates his nearby town has been beseiged by a dragon, a fey creature casts a spell on the caravan and everyone but Ixo is affected turning into a chicken spawning a mini game where Ixo has to round up all the chickens before travelling onwards.
Now say Ixo doesn't mind PVP and says he'd be happy to have pvp in his mishes well about the same time that Ixo is getting his caravan duty mish, Rolf is getting a mish from the thieves guild to pinch Ixo's merchants goods. And when Ixo's ambush triggers, Rolf is asked to join up to help with ambush.  His mish could be to sneak it back to town, take it to a nearby ruined church, but he might just find while rummaging through the merchants goods, a strange statue that he will need to take back to a fence. 
Now Ixo gets back home after caravan duty and fighters guild gives him his share of the cash and he gets a good rep with them. After a few more mishes of similar level, Ixo has the opportunity to handle a mission for The Scarlet Eye, the private investigatory mish which will lead to an instanced dungeon, and may open up a position in The Scarlet Eye leading to a whole other sets of mish types to chose from. 
Feel free to savage .... I whole-heartedly admit its a very rough idea.