Ideas I got from PacCity4 Development thread that I liked and wanted to see if you would consider these:
No "Job" System
Your job is what you do. It's not a tag and it's not a number to be added to your wallet every day. It's not even exclusive with other jobs. It's an action. Do your job.
You can mine ore, process that ore to items, and sell those items. So are you a miner? A factory worker? A shopkeeper? You're none of those, and yet you're all of them. Don't place artificial restrictions on that kind of thing - you could also sell that ore to another player who has access to the right gear to process it, so they can sell it on as shipped items (unusable until sold from a sales case) to someone who has a commercial area to sell them to consumers.
Career Criminality
This was always a fundamental flaw. Theft isn't mutually exclusive with your ability to swing a pickaxe. If you learn to do it, you can steal or pick locks. Since anyone can do it, the punishments should be more severe.
At 1-5 stars, you have a linear scaling jail time (20-60 minutes) which a lawyer can pay to exempt you from. At 6-8 stars (70-90 minutes) a lawyer cannot pay parole. At 9 or 10 stars, you gain a life sentence - if you're jailed, that's it. You get reset and your lot(s) are put up to be sold on the real estate. Of course, past 5 stars, the amount of crime required to gain another star should increase exponentially. If you get repeatedly jailed at 6-8 stars, it should permanently make it easier to gain stars past 5 - so if you have a lot of decent size crime sprees eventually you are going to get that life sentence.
Building
For the love of god don't make players place lots. Holes in the landscape is ridiculous. Make lots with existing ground, and a proper lot purchase system for real estate.
Lot zoning should also be important - to legally sell items you should have to zone your lot as Commercial, which costs as well as purchasing it. To process raw materials it should need to be zoned Industrially, and personal spawns should only work on Residential lots. The lot zoning should stay with the lot even if it transfers owners.
Learning and Skills
To do certain things, one should require certain skills which can be learned.
Learning about Mining should increase the speed at which you mine ore, learning about Engineering should increase the speed at which you produce items and even reduce the ore cost of doing so, learning about Economics should decrease the taxation you pay on sold items, learning about Crime should teach you to pick locks and steal wallets, increasing your Physical capabilities should increase the speed at which you run and how high you jump.
Essentially, multiple areas of study which change the ways you interact with the world. These should be learned by both paying and spending time to actually study them - encourage this with fun "Go to school, dumbass!" propaganda posters!
Studying should be done by spending time on campus for a number of ticks - you just need to visit the campus each tick until you've got the necessary amount of study time accrued, and then you've learned it. You can go and do other things while you study, and if there's multiple campuses you could even learn multiple skills at once if you have the money and can make it to each campus each tick.
Also, you should be able to show someone your CV - essentially, show them what skills you have, in a way you can't lie about. If you want someone with some Engineering qualifications to run your production line, so you use less ore and get things done faster, you don't want them to lie about it.
Variety, variety, variety
A proper inventory system would be a great plus. Limit the amount you can carry so you can't just mine for hours on end, and also open the door to more variety in the items you can use. You could have things like actual usable drugs - say a reflex enhancer that increases your physical capabilities for a set time, or cigarettes that make you look cool and reduce spread with weapons, or food you can actually buy and carry around and eat later, clothing, portable vehicles - there's a lot of things you could do. The fact that the only interesting thing in a cityrp is a gun is its biggest flaw, so fix that.
Hygiene- Requires a hunger system, and it is a bit 'sims-ish' I know, but sometime after eating a player will need to use a toilet brick. If a player fails to do so in time they will soil themself, which mounts an emitter on the player. (Such as flies or green clouds) While in this soiled state they can fined one time by a policeman for public indecency. They will need clean themselves using a bath tub brick.
Automated Starter Hotel- A run-down, cheap hotel that is automated. Most new players are homeless for a long time before they can purchase their own space. An automated hotel would allow them to have a place to stay, for a price paid daily. It would be unattractive, have small rooms, and shared bathrooms. Just a basic place to start until they can afford either a better player-owned apartment/hotel, or their own home.
Garage Car Spawn- Think like APB, or GTA. A garage that players 'store' their cars in and can spawn 1 at any time in game. When a player logs out the vehicle is despawned, instead of most city rp's where the first 20 people who buy a car let them sit around and get used/stolen by everyone else. Only 20 cars can be out at one time, but 60 different people can all own a car and bring them out based on the current number of cars driving around.
Storage Bricks- Lockers and safes that allow players to store items and cash. Criminals can crack these open. Things like lockers are cheap and easily crackable within seconds, but an expensive safe might take minutes to break into
May be asking for too much.