The Sim City series has always fulfilled a dream of mine... to create my own city as I see fit, zoning how I feel will be efficient, taxing at a rate that allows me to profit but doesn't discourage growth.
It's a great series, and I'd say Sim City 4 is the best of the bunch, though it is not as easy to understand as the prior releases. Instead of having a yearly budget to tackle... you're hit with one every month. However, you also get a lot more money than you did in any other version of the game. $500,000 for easy... $200,000 for medium, $100,000 for hard.
This is a far cry from what the prior games would offer. Sim City 3000 had $50,000 for easy, which was a huge jump up from the $20,000 of the games before it.
But even with that half-million on Easy... you can easily find yourself running out of money if you're not careful. You have to be careful how you invest your funds, and make sure that you are not funding your schools and hospitals more than is necessary to service the population. That is a nice feature of the game... you can scale back funding for many types of buildings. On a per-dollar basis, an underfunded school or power plant will produce less education/power... but you will still save money in a small town.
This game is not a 10 however, because a lot of issues and mistakes were only fixed via user modded content.