The somewhat simple and limiting gameplay makes it a bit boring once you rake in profits and subscribers. I got some ideas while playing it.
I wish you could buy better servers to increase the player limit in zones, create a kind of respawn "area" that's connected to a certain respawn point so low-level players don't respawn in the nearby high-level zone, and be allowed to create more flexible monsters and player-classes, which could be combined with Street Wolf's ideas. Maybe even being able to determine drop rates and items.
It'd also be nice to have a graphics generator. Something where you could draw icons for players, items, weapons, monsters and such. Then there's quests and difficulty of them. It'd require quite a big amount of quests, even for a somewhat small area. This could be solved by managing the overall quest difficulty and such in certain zones and towns. Genres would be a nice addition too. Determining whether it's Sci-Fi, Medieval or Modern day could connect to different groups of people, and would impact subscribers and users.
Disasters. Some people remember the faulty coding in a World of Warcraft patch, that led to an outbreak of a new disease. Disasters ranging from things like that to servers exploding or something as simple as an employee dying, which leads me to another thing. It'd be nice to have employee personalities, like their skill in a certain field combined with their monthly or weekly wage.
A monthly wage would cost more for better employees (they have bills to pay too!), while not costing too much at one moment, whereas a weekly wage would cost less to get better employees, but can really siphon your bank account after a while. Maybe being able to buy better-quality software and hardware which would allow you to expand and define the world more easily and flexibly.
Sorry to kinda steal the spotlight Street Wolf, but it's all about the game right? ;)