It seems that you want to create a loap different from others out there, that's good, though you should expect a lot of work. Thinking about new and unique features to a game is always a hard work, and it eventually will be a bit more complex. I didn't played loaps that much, but I think the key to have a successful loap map is to add as much realism as possible.
Ideas: instead of just having those jobs that if you work you receive gold, if you don't work nothing happens; add to this system something more realistic. For example, if you don't work after a day or so, you receive a warning message and your money income will be reduce, after some time happening this you will eventually be fired. On the other hand if you work really hard on the job, your money income will increase, as you get a better rank on that specific job.
add npc villagers a bit of intelligence, rotines and that type of stuff, easily done with GUI, so the city will become more alive. Also, when you commit a crime, if the police has detected you, you get arrested instead of killed.
a suggestion, play a lot of loaps, and see what they have and what they don't, then you would want to add these features to your map, that other loaps don't have.
I can't think of anything else, if I get any idea I'll post here.