Alright, I started off a brand new project from scratch yesterday, for now I've only made this up in a single city (or neighborhood, if you prefer how The Sims 2 calls them), even though I provided the best road network I could, and a huge underground metro, there's still a lot of unemployment in my R$$ - R$$$ zones, I am yet to understand why, anyway here are some pictures:
This is an overall view of the whole city, you can see I made a huge industrial area on the left to make the minimum pollution possible in the actual town, I got a massive demand of hi-tech but I don't know how to upgrade it, it has a perfect water coverage and it's all on high-density. The commercial area is the middle one, next to it is a small landfill, just the minimum to contain the whole garbage of the city; again, the commercial area has got a perfect water coverage and it is all on "high-density". Finally, on the right are the residential and agriculture zones, I ended up mixing them because of the unemployment, but it didn't help at all, so I was thinking to remove them and turn them into residential aswell...
This is a wide look on the industrial zone
This is a close-up on the industrial zone