McLolorzman

In my opinion, I wouldn't use such a structured layout. Restricting your zones to very specific 3x3, 4x4, and 5x5... you're going to see the same buildings over and over and over again. To get the best diversity you need to mix and match zone sizes and densities (as well as load up on some of the great contributions to the STEX). Plus, a grid style as proposed will sent anything interesting the city may have about it down the toilet (in my opinion of course). And I would make commercial dominate my city center instead of industry as shown in the picture there. These are just things I would do, though, but everyone's different. The important thing is to experiment and have fun.